CATALYSTS FOR EPOXIDE CARBONYLATION

20170080409 ยท 2017-03-23

Assignee

Inventors

Cpc classification

International classification

Abstract

The present invention encompasses catalysts for the carbonylation of heterocycles such as ethylene oxide, as well as methods for their use. The catalysts feature Lewis acidic metal complexes having one or more tethered metal-coordinating groups in combination with at least one metal carbonyl species. In preferred embodiments, the inventive catalysts have improved stability when subjected to product separation conditions in continuous ethylene oxide carbonylation processes.

Claims

1. A metal complex for the carbonylation of heterocycles comprising the combination of: i) one or more tethered metal-coordinating moieties, where each metal-coordinating moiety comprises a linker and 1 to 4 metal-coordinating groups; ii) one or more ligands to which the one or more metal-coordinating moieties are covalently tethered, wherein the one or more ligands are coordinated to one or two metal atoms; and iii) at least one metal carbonyl species associated with a metal-coordinating moiety present on the metal complex.

2. The metal complex of claim 1, wherein the one or more ligands to which at least one metal-coordinating moiety is covalently tethered is selected from the group consisting of porphryin ligands and salen ligands.

3. The metal complex of claim 2, wherein metal complex comprises a salen or porphyrin complex of a metal selected from the group consisting of: Zn(II), Cu(II), Mn(II), Co(II), Ru(II), Fe(II), Co(II), Rh(II), Ni(II), Pd(II), Mg(II), Al(III), Cr(III), Fe(III), Co(III), Ti(III), In(III), Ga(III), Mn(III).

4. The metal complex of claim 2, wherein the metal complex comprises a salen or porphyrin complex of aluminum.

5. The metal complex of claim 2, wherein the metal complex comprises a salen or porphyrin complex of chromium.

6. The metal complex of claim 1, wherein a metal-coordinating moiety comprises one or more functional groups containing an atom selected from the group consisting of: phosphorous, nitrogen atom, and boron.

7. A method for the carbonylation of heterocycles comprising contacting a heterocycle and carbon monoxide in the presence of a metal complex of claim 1.

8. The method of claim 7, wherein the heterocycle is an epoxide, aziridine, thiirane, oxetane, lactone, or lactam.

9. The method of claim 8, wherein the heterocycle is ethylene oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0034] The present disclosure encompasses improved catalysts for the carbonylation of epoxides and processes of making and using such catalysts.

[0035] Numerous catalysts competent for the carbonylation of epoxides and other heterocycles are known in the art. Metal carbonyl-Lewis acid catalyst such as those described in U.S. Pat. No. 6,852,865 are among the most active and selective catalysts for epoxide carbonylation, but as noted above, such catalysts can be challenging to adapt to continuous processes where the catalyst must be recovered from the product stream and re-used. Without being bound by theory or thereby limiting the scope of the present invention, it is believed that this may be due to one or more factors including: decomposition of the metal carbonyl during catalyst recovery steps conducted in environments deficient in CO (such as distillation), or due to physical separation of the metal carbonyl component of the catalyst from the Lewis acid component (as may occur during processes such as extraction, nanofiltration, adsorption or precipitation). The current invention improves existing catalyst systems by engineering the ligand on the Lewis acid such that the metal carbonyl and the Lewis acid have improved stability and/or are less likely to disassociate from each other during catalyst recovery. In certain embodiments, such catalysts have further advantages in that they have increased catalytic rates and/or selectivity.

[0036] According to one aspect, the present invention provides carbonylation catalysts comprising the combination of a Lewis-acidic metal complex and a metal carbonyl compound. The Lewis-acidic metal complex in such catalysts contains one or more metal atoms associated with one or more ligands and are characterized in that at least one of the ligands has an additional metal-coordinating moiety covalently bound to it. The purpose of the tethered metal-coordinating moiety is to interact with the metal carbonyl compound. Again, without being bound by theory, it is believed that by providing such a coordinating moiety as part of the Lewis acid, the resulting catalyst may: a) exhibit enhanced stability in low CO environments: b) exhibit better separation characteristics in processes such as adsorption, extraction, or filtration where there may be a tendency for the two components of the catalyst to be separated from each other; c) exhibit increased catalytic activity or selectivity; or any combination of (a) through (c).

[0037] Preferably, the metal-coordinating moiety present in catalysts of the present invention has a carefully selected affinity for the metal carbonyl compound, which together with the Lewis acidic metal complex to which the metal-coordinating moiety is tethered makes up the catalyst. In certain embodiments, the affinity of the coordinating moiety is selected such that under carbonylation reaction conditions where there is a high CO concentration, the metal carbonyl compound dissociates at least partially from the metal-coordinating moiety so that it may act as a nucleophile in the typical fashion. Under conditions of low CO concentration (for example such as might be encountered in a product recovery step such as distillation), the metal carbonyl compound can re-associate with the metal-coordinating moiety thereby preventing further decomposition or loss of the metal carbonyl component of the catalyst.

[0038] It is to be appreciated that the terms catalyst and metal complex are used herein interchangeably, and the term catalyst is not meant to limit the use or preferred stoichiometry of provided metal complexes.

[0039] In other embodiments of provided catalysts, the metal-coordinating moieties may act as a reservoir for additional metal carbonyl equivalents. This can be the case for example where there are a plurality of metal-coordinating groups present on one ligand. If each metal-coordinating group is coordinated to one metal carbonyl complex, then the activity and/or stability of the catalyst can be improved. Such catalysts can be advantageously used in continuous epoxide carbonylation reaction systems where additional metal carbonyl is fed over time to replenish lost or decomposed metal carbonyl.

[0040] In certain embodiments, provided carbonylation catalysts of the present invention include a cationic Lewis-acidic metal complex and at least one anionic metal carbonyl compound balancing the charge of the metal complex.

[0041] In certain embodiments, the Lewis-acidic metal complex has the formula [(L.sup.c).sub.aM.sub.b(L.sup.n).sub.c].sup.z, where: [0042] L.sup.c is a ligand that includes at least one metal-coordinating moiety where, when two or more L.sup.c are present, each may be the same or different; [0043] M is a metal atom where, when two M are present, each may be the same or different; [0044] L.sup.n is optionally present, and if present, is a ligand that does not include a metal-coordinating moiety where, when two or more L.sup.n are present, each may be the same or different; [0045] a is an integer from 1 to 4 inclusive; [0046] b is an integer from 1 to 2 inclusive; [0047] c is an integer from 0 to 6 inclusive; and [0048] z is 0 where the metal complex is neutral or an integer greater than 0 representing the magnitude of cationic charge on the metal complex.

[0049] In certain embodiments, provided metal complexes conform to structure I:

##STR00001##

wherein:

##STR00002##

is a multidentate ligand; [0050] M is a metal atom coordinated to the multidentate ligand; [0051] a is the charge of the metal atom and ranges from 0 to 2; and custom-character(Z).sub.b represents a metal-coordinating moiety, where one or more custom-character(Z).sub.b may be present on the multidentate ligand; [0052] where custom-character is a in er moiety covalently coupled to the multidentate ligand; [0053] Z is a metal-coordinating group covalently coupled to the linker moiety; and [0054] b is the number of metal-coordinating groups coupled to the linker moiety and is an integer between 1 and 4 inclusive;

[0055] In certain embodiments, provided metal complexes conform to structure II:

##STR00003##

where each of custom-character(Z).sub.b and a is as defined above, and each a may be the same or different; and [0056] M.sup.1 is a first metal atom; M.sup.2 is a second metal atom:

##STR00004##

comprises a multidentate ligand system capable of coordinating both metal atoms.

[0057] For sake of clarity, and to avoid confusion between the net and total charge of the metal atoms in complexes I and II and other structures herein, the charge (a.sup.+) shown on the metal atom in complexes I and II above represents the net charge on the metal atom after it has satisfied any anionic sites of the multidentate ligand. For example, if a metal atom in a complex of formula I were Cr(III), and the ligand were porphyrin (a tetradentate ligand with a charge of 2), then the chromium atom would have a net charge of +1, and a would be 1.

[0058] Before more fully describing the provided catalysts, the following section provides a more detailed understanding of what the tethered metal-coordinating moieties are.

I. Metal-Coordinating Moieties

[0059] As described above, inventive catalysts of the present invention include Lewis-acidic metal complexes featuring one or more tethered metal-coordinating moieties. Each metal-coordinating moiety denoted generically herein as custom-character(Z).sub.b comprises a linker custom-character coupled to at least one metal-coordinating group Z, where b denotes the number of metal-coordinating groups present on a single linker moiety. Thus, a single metal-coordinating moiety may contain two or more metal-coordinating groups.

[0060] In some embodiments, there may be one or more metal-coordinating moieties custom-character(Z).sub.b tethered to a given metal complex; each metal-coordinating moiety may itself contain more than one metal-coordinating group Z. In certain embodiments, each metal-coordinating moiety contains only one metal-coordinating group (i.e. b=1). In some embodiments, each metal-coordinating moiety contains more than one metal-coordinating groups (i.e. b>1). In certain embodiments, a metal-coordinating moiety contains two metal-coordinating groups (i.e. b=2). In certain embodiments, a metal-coordinating moiety contains three metal-coordinating groups (i.e. b=3). In certain embodiments, a metal-coordinating moiety contains four metal-coordinating groups (i.e. b=4). In certain embodiments where more than one metal-coordinating group is present on a metal-coordinating moiety, the metal-coordinating groups are the same. In some embodiments where more than one metal-coordinating group is present on a metal-coordinating moiety, two or more of the metal-coordinating groups are different.

Ia. Linkers

[0061] In certain embodiments, a linker custom-character may comprise a bond. In this case, the metal-coordinating group Z is bonded directly to the ligand. To avoid the need to arbitrarily define where a ligand ends and a tether begins, it is to be understood that if a Z group is bonded directly to an atom that is typically regarded as part of the parent structure of the ligand, then the linker custom-character is to be regarded as comprising a bond. In certain embodiments, when custom-character comprises a bond, b is 1.

[0062] In certain embodiments, each linker custom-character contains 1-30 atoms including at least one carbon atom, and optionally one or more atoms selected from the group consisting of N, O, S, Si, B, and P.

[0063] In certain embodiments, a linker is an optionally substituted C.sub.2-30 aliphatic group wherein one or more methylene units are optionally and independently replaced by -Cy-, NR.sup.y, N(R.sup.y)C(O), C(O)N(R.sup.y), O, C(O), OC(O), C(O)O, S, SO, SO.sub.2, C(S), C(NR.sup.y), or NN, wherein: [0064] each -Cy- is independently an optionally substituted 5-8 membered bivalent, saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or an optionally substituted 8-10 membered bivalent saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and [0065] each R.sup.y is independently H, or an optionally substituted radical selected from the group consisting of C.sub.1-6 aliphatic, phenyl, a 3-7 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, a 5-6 membered heteroaryl ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur, and an 8- to 10-membered aryl ring.

[0066] In certain embodiments, a linker custom-character is a C.sub.3-C.sub.12 aliphatic group substituted with one or more moieties selected from the group consisting of halogen, NO.sub.2, CN, SR.sup.y, S(O)R.sup.y, S(O).sub.2R.sup.y, NR.sup.yC(O)R.sup.y, OC(O)R.sup.y, CO.sub.2R, NCO, N.sub.3, OR.sup.4, OC(O)N(R.sup.y).sub.2, N(R.sup.y).sub.2, NR.sup.yC(O)R.sup.y, and NR.sup.yC(O)OR.sup.y, where each R.sup.y and R.sup.4 is independently as defined herein and described in classes and subclasses herein.

[0067] In certain embodiments, a linker custom-character is an optionally substituted C.sub.3-C.sub.30 aliphatic group. In certain embodiments, a linker is an optionally substituted C.sub.4-24 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.4-C.sub.20 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.4-C.sub.12 aliphatic group. In certain embodiments, a linker is an optionally substituted C.sub.4-10 aliphatic group. In certain embodiments, a linker is an optionally substituted C.sub.4-8 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.4-C.sub.6 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.6-C.sub.12 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.8 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.7 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.6 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.5 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.4 aliphatic group. In certain embodiments, a linker moiety is an optionally substituted C.sub.3 aliphatic group. In certain embodiments, an aliphatic group in the linker moiety is an optionally substituted straight alkyl chain. In certain embodiments, the aliphatic group is an optionally substituted branched alkyl chain. In some embodiments, a linker moiety is a C.sub.4 to C.sub.20 alkyl group having one or more methylene groups replaced by C(R.sup.).sub.2 wherein R.sup. is as defined above. In certain embodiments, a linker custom-character consists of a bivalent aliphatic group having 4 to 30 carbons including one or more C.sub.1-4 alkyl substituted carbon atoms. In certain embodiments, a linker moiety consists of a bivalent aliphatic group having 4 to 30 carbons including one or more gem-dimethyl substituted carbon atoms.

[0068] In certain embodiments, a linker custom-character includes one or more optionally substituted cyclic elements selected from the group consisting of saturated or partially unsaturated carbocyclic, aryl, heterocyclic, or heteroaryl. In certain embodiments, a linker moiety consists of the substituted cyclic element. In some embodiments, the cyclic element is part of a linker with one or more non-ring heteroatoms or optionally substituted aliphatic groups comprising other parts of the linker moiety.

[0069] In certain embodiments, structural constraints are built into a linker moiety to control the disposition and orientation of one or more metal-coordinating groups near a metal center of a metal complex. In certain embodiments, such structural constraints are selected from the group consisting of cyclic moieties, bicyclic moieties, bridged cyclic moieties and tricyclic moieties. In some embodiments, such structural constraints are the result of acyclic steric interactions. In certain embodiments, steric interactions due to syn-pentane, gauche-butane, and/or allylic strain in a linker moiety, bring about structural constraints that affect the orientation of a linker and one or more metal-coordinating groups. In certain embodiments, structural constraints are selected from the group consisting of cis double bonds, trans double bonds, cis allenes, trans allenes, and triple bonds. In some embodiments, structural constraints are selected from the group consisting of substituted carbons including geminally disubstituted groups such as sprirocyclic rings, gem dimethyl groups, gem diethyl groups, and gem diphenyl groups. In certain embodiments, structural constraints are selected from the group consisting of heteratom-containing functional groups such as sulfoxides, amides, and oximes.

[0070] In certain embodiments, linker moieties are selected from the group consisting of:

##STR00005## ##STR00006##

[0071] wherein each s is independently 0-6, t is 0-4, R.sup.y is defined above and described in classes and subclasses herein, * represents the site of attachment to a ligand, and each # represents a site of attachment of a metal-coordinating group.

[0072] In some embodiments, s is 0. In some embodiments, s is 1. In some embodiments, s is 2. In some embodiments, s is 3. In some embodiments, s is 4. In some embodiments, s is 5. In some embodiments, s is 6.

[0073] In some embodiments, t is 1. In some embodiments, t is 2. In some embodiments, t is 3. In some embodiments, t is 4.

[0074] In certain embodiments, there is at least one metal-coordinating moiety tethered to the multidentate ligand. In certain embodiments, there are 1 to 8 such metal-coordinating moieties tethered to the multidentate ligand. In certain embodiments, there are 1 to 4 such metal-coordinating moieties tethered to the multidentate ligand. In certain embodiments, there is 1 such metal-coordinating moiety tethered to the multidentate ligand. In certain embodiments, there are 2 such metal-coordinating moieties tethered to the multidentate ligand. In certain embodiments, there are 3 such metal-coordinating moieties tethered to the multidentate ligand. In certain embodiments, there are 4 such metal-coordinating moieties tethered to the multidentate ligand.

Ib. Metal-Coordinating Groups

[0075] The purpose of metal-coordinating groups in provided catalysts is to coordinate with the metal atom in a metal carbonyl compound. As described above, metal-coordinating group is tethered to a ligand, said ligand being coordinated to another metal atom (e.g. not the metal in the metal carbonyl). A large number of neutral coordinating ligands are known in the art. In certain embodiments, a metal-coordinating group in catalysts of the present invention is simply a tethered analog of a group known to coordinate to a metal carbonyl compound.

[0076] In certain embodiments, one or more tethered metal-coordinating groups (Z) comprise neutral functional groups containing one or more atoms selected from phosphorous, nitrogen, and boron.

Neutral Nitrogen-Containing Metal-Coordinating Groups

[0077] In certain embodiments, a tethered metal-coordinating group is a neutral nitrogen containing functional group. In certain embodiments, a tethered metal-coordinating group is selected from the group consisting of: amine, hydroxyl amine, N-oxide, urea, carbamate, imine, oxime, amidine, guanidine, bis-guanidine, amidoxime, enamine, azide, cyanate, azo, hydrazine, and nitroso functional groups. In certain embodiments, a tethered metal-coordinating group is a nitrogen-containing heterocycle or heteroaryl.

[0078] In certain embodiments, one or more tethered metal-coordinating groups (Z) on the Lewis-acidic metal complexes (i.e. complexes of formulae I or II or any of the embodiments, classes or subclasses thereof described herein) are neutral nitrogen-containing moieties. In some embodiments, such moieties include one or more of the structures in Table Z-1:

TABLE-US-00001 TABLE Z-1 [00007]embedded image [00008]embedded image [00009]embedded image [00010]embedded image [00011]embedded image [00012]embedded image [00013]embedded image [00014]embedded image [00015]embedded image [00016]embedded image [00017]embedded image [00018]embedded image [00019]embedded image [00020]embedded image [00021]embedded image [00022]embedded image [00023]embedded image [0079] or a combination of two or more of these, [0080] wherein: [0081] each R.sup.1 and R.sup.2 is independently hydrogen or an optionally substituted radical selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring; wherein R.sup.1 and R.sup.2 can be taken together with intervening atoms to form one or more optionally substituted rings optionally containing one or more additional heteroatoms; [0082] each R.sup.3 is independently hydrogen or an optionally substituted radical selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring; wherein an R.sup.3 group can be taken with an R.sup.1 or R.sup.2 group to form one or more optionally substituted rings; and [0083] each R.sup.4 is independently hydrogen, a hydroxyl protecting group, or an optionally substituted radical selected from the group consisting of C.sub.1-20 acyl; C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring.

[0084] In certain embodiments, each R.sup.1 group is the same. In other embodiments, R.sup.1 groups are different. In certain embodiments, R.sup.1 is hydrogen. In some embodiments, R.sup.1 is an optionally substituted radical selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic, 5- to 14-membered heteroaryl, phenyl, 8- to 10-membered aryl and 3- to 7-membered heterocyclic. In some embodiments, R.sup.1 is an optionally substituted radical selected from the group consisting of a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring.

[0085] In certain embodiments, R.sup.1 is an optionally substituted radical selected from the group consisting of C.sub.1-12 aliphatic and C.sub.1-12 heteroaliphatic. In some embodiments, R.sup.1 is optionally substituted C.sub.1-20 aliphatic. In some embodiments, R.sup.1 is optionally substituted C.sub.1-12 aliphatic. In some embodiments, R.sup.1 is optionally substituted C.sub.1-6 aliphatic. In some embodiments, R.sup.1 is optionally substituted C.sub.1-20 heteroaliphatic. In some embodiments, R.sup.1 is optionally substituted C.sub.1-12 heteroaliphatic. In some embodiments, R.sup.1 is optionally substituted phenyl. In some embodiments, R.sup.1 is optionally substituted 8- to 10-membered aryl. In some embodiments, R.sup.1 is an optionally substituted 5- to 6-membered heteroaryl group. In some embodiments, R.sup.1 is an optionally substituted 8- to 14-membered polycyclic heteroaryl group. In some embodiments, R.sup.1 is optionally substituted 3- to 8-membered heterocyclic.

[0086] In certain embodiments, each R.sup.1 is independently hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, optionally substituted phenyl, or optionally substituted benzyl. In certain embodiments, R.sup.1 is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, phenyl, or benzyl. In some embodiments, R.sup.1 is butyl. In some embodiments, R.sup.1 is isopropyl. In some embodiments, R.sup.1 is neopentyl. In some embodiments, R.sup.1 is perfluoro. In some embodiments, R.sup.1 is CF.sub.2CF.sub.3. In some embodiments, R.sup.1 is phenyl. In some embodiments, R.sup.1 is benzyl.

[0087] In certain embodiments, each R.sup.2 group is the same. In other embodiments, R.sup.2 groups are different. In certain embodiments, R.sup.2 is hydrogen. In some embodiments, R.sup.2 is an optionally substituted radical selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic, 5- to 14-membered heteroaryl, phenyl, 8- to 10-membered aryl and 3- to 7-membered heterocyclic. In some embodiments, R.sup.2 is an optionally substituted radical selected from the group consisting of a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring.

[0088] In certain embodiments, R.sup.2 is an optionally substituted radical selected from the group consisting of C.sub.12 aliphatic and C.sub.1-12 heteroaliphatic. In some embodiments, R.sup.2 is optionally substituted C.sub.1-20 aliphatic. In some embodiments, R.sup.2 is optionally substituted C.sub.1-12 aliphatic. In some embodiments, R.sup.2 is optionally substituted C.sub.1-6 aliphatic. In some embodiments, R.sup.2 is optionally substituted C.sub.1-20 heteroaliphatic. In some embodiments, R.sup.2 is optionally substituted C.sub.1-12 heteroaliphatic. In some embodiments, R.sup.2 is optionally substituted phenyl. In some embodiments, R.sup.2 is optionally substituted 8- to 10-membered aryl. In some embodiments, R.sup.2 is an optionally substituted 5- to 6-membered heteroaryl group. In some embodiments, R.sup.2 is an optionally substituted 8- to 14-membered polycyclic heteroaryl group. In some embodiments, R.sup.2 is optionally substituted 3- to 8-membered heterocyclic.

[0089] In certain embodiments, each R.sup.2 is independently hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, optionally substituted phenyl, or optionally substituted benzyl. In certain embodiments, R.sup.2 is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, phenyl, or benzyl. In some embodiments, R.sup.2 is butyl. In some embodiments, R.sup.2 is isopropyl. In some embodiments, R.sup.2 is neopentyl. In some embodiments, R.sup.2 is perfluoro. In some embodiments, R.sup.2 is CF.sub.2CF.sub.3. In some embodiments, R.sup.2 is phenyl. In some embodiments, R.sup.2 is benzyl.

[0090] In certain embodiments, each R.sup.1 and R.sup.2 are hydrogen. In some embodiments, each R.sup.1 is hydrogen each and each R.sup.2 is other than hydrogen. In some embodiments, each R.sup.2 is hydrogen each and each R.sup.1 is other than hydrogen.

[0091] In certain embodiments, R.sup.1 and R.sup.2 are both methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, phenyl, or benzyl. In some embodiments, R.sup.1 and R.sup.2 are each butyl. In some embodiments, R.sup.1 and R.sup.2 are each isopropyl. In some embodiments, R.sup.1 and R.sup.2 are each perfluoro. In some embodiments, R.sup.1 and R.sup.2 are CF.sub.2CF.sub.3. In some embodiments, R.sup.1 and R.sup.2 are each phenyl. In some embodiments, R.sup.1 and R.sup.2 are each benzyl.

[0092] In some embodiments, R.sup.1 and R.sup.2 are taken together with intervening atoms to form one or more optionally substituted carbocyclic, heterocyclic, aryl, or heteroaryl rings. In certain embodiments, R.sup.1 and R.sup.2 are taken together to form a ring fragment selected from the group consisting of: C(R.sup.y).sub.2, C(R.sup.y).sub.2C(R.sup.y).sub.2, C(R.sup.y).sub.2C(R.sup.y).sub.2C(R.sup.y).sub.2, C(R.sup.y).sub.2OC(R.sup.y).sub.2, and C(R.sup.y).sub.2NR.sup.yC(R.sup.y).sub.2, wherein R.sup.y is as defined above. In certain embodiments, R.sup.1 and R.sup.2 are taken together to form a ring fragment selected from the group consisting of: CH.sub.2, CH.sub.2CH.sub.2, CH.sub.2CH.sub.2CH.sub.2, CH.sub.2OCH.sub.2, and CH.sub.2NR.sup.yCH.sub.2. In some embodiments, R.sup.1 and R.sup.2 are taken together to form an unsaturated linker moiety optionally containing one or more additional heteroatoms. In some embodiments, the resulting nitrogen-containing ring is partially unsaturated. In certain embodiments, the resulting nitrogen-containing ring comprises a fused polycyclic heterocycle.

[0093] In certain embodiments, R.sup.3 is H. In certain embodiments, R.sup.3 is an optionally substituted radical selected from C.sub.1-20 aliphatic, C.sub.1-20 heteroaliphatic, 5- to 14-membered heteroaryl, phenyl, 8- to 10-membered aryl, or 3- to 7-membered heterocyclic. In some embodiments, R.sup.3 is an optionally substituted radical selected from the group consisting of a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring. In certain embodiments, R.sup.3 is optionally substituted C.sub.1-12 aliphatic. In some embodiments, R.sup.3 is optionally substituted C.sub.1-6 aliphatic. In certain embodiments, R.sup.3 is optionally substituted phenyl.

[0094] In certain embodiments, R.sup.3 is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, phenyl or benzyl. In some embodiments, R.sup.3 is butyl. In some embodiments, R.sup.3 is isopropyl. In some embodiments, R.sup.3 is perfluoro. In some embodiments, R.sup.3 is CF.sub.2CF.sub.3.

[0095] In some embodiments, one or more R.sup.1 or R.sup.2 groups are taken together with R.sup.3 and intervening atoms to form an optionally substituted heterocyclic or heteroaryl ring. In certain embodiments, R.sup.1 and R.sup.3 are taken together to form an optionally substituted 5- or 6-membered ring. In some embodiments, R.sup.2 and R.sup.3 are taken together to form an optionally substituted 5- or 6-membered ring optionally containing one or more heteroatoms in addition to any heteroatoms already present in the group to which R.sup.2 and R.sup.3 are attached. In some embodiments, R.sup.1, R.sup.2, and R.sup.3 are taken together to form an optionally substituted fused ring system. In some embodiments, such rings formed by combinations of any of R.sup.1, R.sup.2, and R.sup.3 are partially unsaturated or aromatic.

[0096] In certain embodiments, R.sup.4 is hydrogen. In some embodiments, R.sup.4 is an optionally substituted radical selected from the group consisting of C.sub.1-12 aliphatic, phenyl, 8- to 10-membered aryl, and 3- to 8-membered heterocyclic or heteroaryl. In certain embodiments, R.sup.4 is a C.sub.1-12 aliphatic. In certain embodiments, R.sup.4 is a C.sub.1-6 aliphatic. In some embodiments, R.sup.4 is an optionally substituted 8- to 10-membered aryl group. In certain embodiments, R.sup.4 is optionally substituted C.sub.1-12 acyl or in some embodiments, optionally substituted C.sub.1-6 acyl. In certain embodiments, R.sup.4 is optionally substituted phenyl. In some embodiments, R.sup.4 is a hydroxyl protecting group. In some embodiments, R.sup.4 is a silyl-containing hydroxyl protecting group. In some embodiments, R.sup.4 is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, allyl, phenyl, or benzyl.

[0097] In certain embodiments, R.sup.1 and R.sup.4 are taken together with intervening atoms to form one or more optionally substituted heterocyclic or heteroaryl rings optionally containing one or more heteroatoms in addition to any heteroatoms already present in the group to which R.sup.1 and R.sup.4 are attached.

[0098] In some embodiments, a metal-coordinating functional group is an N-linked amino group:

##STR00024##

R.sup.2, wherein R.sup.1 and R.sup.2 are as defined above and described in classes and subclasses herein.

[0099] In some embodiments, a metal-coordinating N-linked amino group is selected from the group consisting of:

##STR00025## ##STR00026##

[0100] In some embodiments, one or more metal-coordinating functional groups is an N-linked hydroxyl amine derivative:

##STR00027##

wherein R.sup.1 and R.sup.4 are as defined above and described in classes and subclasses herein.

[0101] In certain embodiments, one or more metal-coordinating N-linked hydroxyl amine functional groups are selected from the group consisting of:

##STR00028##

[0102] In some embodiments, a metal-coordinating functional group in a provided metal complex is an amidine. In certain embodiments, such metal-coordinating amidine functional groups are selected from:

##STR00029##

[0103] wherein each of R.sup.1, R.sup.2, and R.sup.3 is as defined above and described in classes and subclasses herein.

[0104] In certain embodiments, a metal-coordinating functional group is an N-linked amidine:

##STR00030##

wherein each of R.sup.1, R.sup.2, and R.sup.3 is as defined above and described in classes and subclasses herein. In certain embodiments, such N-linked amidine groups are selected from the group consisting of:

##STR00031##

[0105] In certain embodiments, metal-coordinating functional groups are amidine moieties linked through the imine nitrogen:

##STR00032##

wherein each of R.sup.1, R.sup.2, and R.sup.3 is as defined above and described in classes and subclasses herein. In certain embodiments, such imine-linked amidine metal-coordinating functional groups are selected from the group consisting of:

##STR00033##

[0106] In certain embodiments, metal-coordinating functional groups are amidine moieties linked through a carbon atom:

##STR00034##

wherein each of R.sup.1, R.sup.2, and R.sup.3 is as defined above and described in classes and subclasses herein. In certain embodiments, such carbon-linked amidine groups are selected from the group consisting of:

##STR00035## ##STR00036##

[0107] In some embodiments, one or more metal-coordinating functional groups is a carbamate. In certain embodiments, a carbamate is N-linked:

##STR00037##

wherein each of R.sup.1 and R.sup.2 is as defined above and described in classes and subclasses herein. In some embodiments, a carbamate is O-linked:

##STR00038##

wherein each of R.sup.1 and R.sup.2 is as defined above and described in classes and subclasses herein.

[0108] In some embodiments, R.sup.2 is selected from the group consisting of: methyl, t-butyl, t-amyl, benzyl, adamantyl, allyl, 4-methoxycarbonylphenyl, 2-(methylsulfonyl)ethyl, 2-(4-biphenylyl)-prop-2-yl, 2-(trimethylsilyl)ethyl, 2-bromoethyl, and 9-fluorenylmethyl.

[0109] In some embodiments, at least one metal-coordinating group is a guanidine or bis-guanidine group:

##STR00039##

[0110] wherein each R.sup.1 and R.sup.2 is as defined above and described in classes and subclasses herein.

[0111] In some embodiments, each R.sup.1 and R.sup.2 is independently hydrogen or optionally substituted C.sub.1-20 aliphatic. In some embodiments, each R.sup.1 and R.sup.2 is independently hydrogen or optionally substituted C.sub.1-10 aliphatic. In some embodiments, any two or more R.sup.1 or R.sup.2 groups are taken together with intervening atoms to form one or more optionally substituted carbocyclic, heterocyclic, aryl, or heteroaryl rings. In certain embodiments, R.sup.1 and R.sup.2 groups are taken together to form an optionally substituted 5- or 6-membered ring. In some embodiments, three or more R.sup.1 and/or R.sup.2 groups are taken together to form an optionally substituted fused ring system.

[0112] In certain embodiments, where a metal-coordinating functional group is a guanidine or bis guanidine moiety, it is selected from the group consisting of:

##STR00040## ##STR00041##

[0113] In some embodiments, a metal-coordinating functional group is a urea:

##STR00042##

wherein each R.sup.1 and R.sup.2 is independently as defined above and described in classes and subclasses herein.

[0114] In certain embodiments, metal-coordinating functional groups are oxime or hydrazone groups:

##STR00043##

wherein each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is as defined above and described in classes and subclasses herein.

[0115] In some embodiments, a metal-coordinating functional group is an N-oxide derivative:

##STR00044##

wherein each of R.sup.1 and R.sup.2 is as defined above and described in classes and subclasses herein.

[0116] In certain embodiments, an N-oxide metal-coordinating group is selected from the group consisting of:

##STR00045## ##STR00046##

[0117] In certain embodiments, one or more tethered coordination groups (Z) comprises a nitrile group, CN. In certain embodiments, one or more tethered coordination groups (Z) comprises an azide group, N.sub.3. In certain embodiments, one or more tethered coordination groups (Z) comprises a cyanate group, OCN. In certain embodiments, one or more tethered coordination groups (Z) comprises a nitroso group, NO.

[0118] In certain embodiments, one or more tethered coordination groups (Z) comprises a neutral nitrogen-containing heterocycle or heteroaryl. In certain embodiments, one or more tethered coordination groups (Z) comprises a neutral nitrogen-containing heterocycle or heteroaryl selected from the group consisting of:

##STR00047## [0119] wherein R.sup.1 is as defined above and in the classes and subclasses herein, and [0120] R.sup.8 may be present on one or more substitutable carbon atoms, wherein each occurrence of R.sup.8 is independently selected from the group consisting of: halogen, NO.sub.2, CN, SR.sup.y, S(O)R.sup.y, S(O).sub.2R.sup.y, NR.sup.yC(O)R.sup.y, OC(O)R.sup.y, CO.sub.2R.sup.y, NCO, N.sub.3, OR.sup.4, OC(O)N(R.sup.y).sub.2, N(R.sup.y).sub.2, NR.sup.yC(O)R.sup.y, NR.sup.yC(O)OR.sup.y; or an optionally substituted radical selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; a 3- to 8-membered saturated or partially unsaturated monocyclic carbocycle; a 7- to 14-membered saturated or partially unsaturated polycyclic carbocycle; a 5- to 6-membered monocyclic heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; an 8- to 14-membered polycyclic heteroaryl ring having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 3- to 8-membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur; a 6- to 14-membered saturated or partially unsaturated polycyclic heterocycle having 1-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur; phenyl; or an 8- to 14-membered polycyclic aryl ring; wherein each R.sup.4 and R.sup.y is independently as defined above and described in classes and subclasses herein, and where two or more adjacent R.sup.8 groups can be taken together to form an optionally substituted saturated, partially unsaturated, or aromatic 5- to 12-membered ring containing 0 to 4 heteroatoms;

Phosphorous-Containing Coordinating Groups

[0121] In certain embodiments, one or more tethered metal-coordinating groups (Z) on provided metal complexes (i.e. complexes of formulae I or II or any of the embodiments, classes or subclasses thereof described herein) is a neutral phosphorous-containing functional group:

[0122] In certain embodiments, a phosphorous-containing functional group is chosen from the group consisting of: phosphines (PR.sup.y.sub.2); phosphine oxides P(O)(R.sup.y).sub.2; phosphinites P(OR.sup.4)(R.sup.y).sub.2; phosphonites P(OR.sup.4).sub.2R.sup.y; phosphites P(OR.sup.4).sub.3; phosphinates OP(OR.sup.4)(R.sup.y).sub.2; phosphonates; OP(OR.sup.4).sub.2R.sup.y; and phosphates OP(OR.sup.4).sub.3; where a phosphorous-containing functional group may be linked to a metal complex through any available position (e.g. direct linkage via the phosphorous atom, linkage through an aliphatic or aromatic group attached to the phosphorous atom or in some cases via an oxygen atom or an aliphatic or aromatic group attached to an oxygen atom), wherein each R.sup.4 and R.sup.y is independently as defined above and described in classes and subclasses herein

[0123] In certain embodiments, a phosphorous-containing functional group is chosen from the group consisting of:

##STR00048## [0124] or a combination of two or more of these [0125] wherein each R.sup.1, R.sup.2, and R.sup.4 is as defined above and described in classes and subclasses herein, both singly and in combination; and where two R.sup.4 groups can be taken together with intervening atoms to form an optionally substituted ring optionally containing one or more heteroatoms, or an R.sup.4 group can be taken with an R.sup.1 or R.sup.2 group to form an optionally substituted carbocyclic, heterocyclic, heteroaryl, or aryl ring.

[0126] In some embodiments, phosphorous containing functional groups include those disclosed in The Chemistry of Organophosphorus Compounds. Volume 4. Ter- and Quincquevalent Phosphorus Acids and their Derivatives. The Chemistry of Functional Group Series Edited by Frank R. Hartley (Cranfield University, Cranfield, U.K.). Wiley: New York. 1996. ISBN 0-471-95706-2, the entirety of which is hereby incorporated herein by reference.

[0127] In certain embodiments, phosphorous containing functional groups have the formula:


(V).sub.b[(R.sup.9R.sup.10R.sup.11P).sup.+].sub.nW.sup.n, wherein: [0128] V is O, N, or NR.sup.z; [0129] b is 1 or 0; [0130] each of R.sup.9, R.sup.10, and R.sup.11 are independently present or absent and, if present, are independently selected from the group consisting of optionally substituted C.sub.1-C.sub.20 aliphatic, optionally substituted phenyl, optionally substituted C.sub.8-C.sub.14 aryl, optionally substituted 3- to 14-membered heterocyclic, optionally substituted 5- to 14-membered heteroaryl, halogen, O, OR.sup.z, NR.sup.z, and N(R.sup.z).sub.2, where R.sup.z is hydrogen, or an optionally substituted C.sub.1-C.sub.20 aliphatic, optionally substituted phenyl, optionally substituted 8- to 14-membered aryl, optionally substituted 3- to 14-membered heterocyclic, or optionally substituted 5- to 14-membered heteroaryl; [0131] W is any anion; and [0132] n is an integer from 1 to 4, inclusive

[0133] In some embodiments, metal-coordinating functional group is a phosphonate group:

##STR00049##

wherein each R.sup.1, R.sup.2, and R.sup.4 is independently as defined above and described in classes and subclasses herein, both singly and in combination.

[0134] In specific embodiments, a phosphonate metal-coordinating functional group is selected from the group consisting of:

##STR00050##

[0135] In some embodiments, a metal-coordinating functional group is a phosphonic diamide group:

##STR00051##

wherein each R.sup.1, R.sup.2, and R.sup.4 is independently as defined above and described in classes and subclasses herein. In certain embodiments, each R.sup.1 and R.sup.2 group in a phosphonic diamide is methyl.

[0136] In some embodiments, a metal-coordinating functional group is a phosphine group:

##STR00052##

wherein R.sup.1, and R.sup.2 are as defined above and described in classes and subclasses herein, both singly and in combination.

[0137] In specific embodiments, a phosphine functional group is selected from the group consisting of:

##STR00053## [0138] where each R.sup.8 is independently as defined above and in the classes and subclasses herein.

[0139] In some embodiments, a metal-coordinating functional group is a phosphite group:

##STR00054##

wherein each R.sup.4 is independently as defined above and described in classes and subclasses herein, both singly and in combination.

[0140] In specific embodiments, a phosphite metal-coordinating functional group is selected from the group consisting of:

##STR00055## ##STR00056## [0141] where each occurrence of R.sup.8 is as defined above and in the classes and subclasses herein.

Boron-Containing Coordinating Groups

[0142] In certain embodiments, one or more tethered metal-coordinating groups (Z) on provided metal complexes (i.e. complexes of formulae I or II or any of the embodiments, classes or subclasses thereof described herein) is a neutral boron-containing functional group.

[0143] In certain embodiments, a boron-containing functional group is chosen from the group consisting of: B(OR.sup.4).sub.2; OB(R.sup.y)OR.sup.4; B(R.sup.y)OR.sup.4OB(R.sup.y).sub.2 wherein each R.sup.4 and R.sup.y is independently as defined above and described in classes and subclasses herein and where the boron-containing functional group may be linked to the metal complex through any available position (e.g. direct linkage via the boron atom, linkage through an aliphatic or aromatic group attached to the boron atom or in some cases via an oxygen atom or an aliphatic or aromatic group attached to an oxygen atom),

II. The Lewis Acidic Metal Complex

[0144] As described above, in certain embodiments the catalysts of the present invention comprise metal-containing Lewis acid complexes containing one or more ligands. While many examples and embodiments herein are focused on the presence of a single multidentate ligand in such complexes, this is not a limiting principle of the present invention and it is to be understood that two or more mono- or multidentate ligands may also be used, when two or more ligands are used, they need not all be substituted with tethered metal-coordinating moieties, only one ligand may be so substituted, or more than one may be substituted with one or more metal-coordinating moieties.

IIa. Ligands in the Acidic Metal Complexes

[0145] Suitable multidentate ligands for the metal-containing Lewis acids include, but are not limited to: porphyrin derivatives 1, salen derivatives 2, dibenzotetramethyltetraaza[14]annulene (tmtaa) derivatives 3, phthalocyaninate derivatives 4, derivatives of the Trost ligand 5, and tetraphenylporphyrin derivatives 6. In certain embodiments, the multidentate ligand is a salen derivative. In other embodiments, the multidentate ligand is a tetraphenylporphyrin derivative.

##STR00057## ##STR00058##

[0146] where each of R.sup.c, R.sup.d, R.sup.a, R.sup.1a, R.sup.2a, R.sup.3a, R.sup.1a, R.sup.2a, R.sup.3a, and R.sup.4a is as defined and described in the classes and subclasses herein.

[0147] In certain embodiments, catalysts of the present invention comprise metal-porphinato complexes. In some embodiments,

##STR00059##

is a metal-porpinato complex. In certain embodiments, the moiety

##STR00060##

has the structure:

##STR00061## [0148] where each of M and a is as defined above and described in the classes and subclasses herein, and [0149] R.sup.d at each occurrence is inndpendently a metal-coordinating moiety (custom-character(Z).sub.b), hydrogen, halogen, OR.sup.4, N(R.sup.y).sub.2, SR, CN, NO.sub.2, SO.sub.2R.sup.y, SOR.sup.y, SO.sub.2N(R.sup.y).sub.2; CNO, NRSO.sub.2R.sup.y, NCO, N.sub.3, SiR.sub.3; or an optionally substituted group selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur, where two or more R.sup.d groups may be taken together to form one or more optionally substituted rings, where each R.sup.y is independently hydrogen, an optionally substituted group selected the group consisting of acyl; carbamoyl, arylalkyl; 6- to 10-membered aryl; C.sub.1-12 aliphatic; C.sub.1-12 heteroaliphatic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; an oxygen protecting group; and a nitrogen protecting group; or two R.sup.y on the same nitrogen atom are taken with the nitrogen atom to form an optionally substituted 4- to 7-membered heterocyclic ring having 0-2 additional heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; and [0150] each R.sup.4 is H, a hydroxyl protecting group or R.sup.y.

[0151] In certain embodiments, the multidentate ligand is a porphyrin moiety. Examples include, but are not limited to:

##STR00062## ##STR00063##

[0152] where M, a, custom-character(Z).sub.b, and R.sup.d are as defined above and in the classes and subclasses herein,

[0153] and So, is an optionally present coordinated solvent molecule, such as an ether, epoxide, DMSO, amine, or other Lewis basic moiety.

[0154] In certain embodiments, the moiety

##STR00064##

has the structure:

##STR00065##

where M, a, and R.sup.d are as defined above and in the classes and subclasses herein.

[0155] In certain embodiments, the multidentate ligand is an optionally substituted tetraphenyl porphyrin. Suitable examples include, but are not limited to:

##STR00066## ##STR00067## ##STR00068##

where M, a, R.sup.d, So, and custom-character(Z).sub.b are as defined above and described in the classes and subclasses herein.

[0156] In certain embodiments, the moiety

##STR00069##

has the structure:

##STR00070##

where M, a, and R.sup.d are as defined above and in the classes and subclasses herein.

[0157] In certain embodiments, catalysts of the present invention comprise metallo salenate complexes. In certain embodiments, the moiety

##STR00071##

has the structure:

##STR00072##

wherein: [0158] M and a are as defined above and in the classes and subclasses herein; [0159] R.sup.1a, R.sup.1a, R.sup.2a, R.sup.2a, R.sup.3a, and R.sup.3a are independently a metal-coordinating moiety (custom-character(Z).sub.b), hydrogen, halogen, OR.sup.4, N(R.sup.y).sub.2, SR, CN, NO.sub.2, SO.sub.2R.sup.y, SOR, SO.sub.2N(R.sup.y).sub.2; CNO, NRSO.sub.2R.sup.y, NCO, N.sub.3, SiR.sub.3; or an optionally substituted group selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; wherein each R, R.sup.4, and R.sup.y is independently as defined above and described in classes and subclasses herein, [0160] wherein any of (R.sup.2a and R.sup.3a), (R.sup.2a and R.sup.3a), (R.sup.1a and R.sup.2a), and (R.sup.1a and R.sup.2a) may optionally be taken together with the carbon atoms to which they are attached to form one or more rings which may in turn be substituted with one or more R groups; and [0161] R.sup.4a is selected from the group consisting of:

##STR00073##

where [0162] R.sup.c at each occurrence is independently a metal-coordinating moiety (custom-character(Z).sub.b), hydrogen, halogen, OR, N(R.sup.y).sub.2, SR, CN, NO.sub.2, SO.sub.2R.sup.y, SOR.sup.y, SO.sub.2N(R.sup.y).sub.2; CNO, NRSO.sub.2R.sup.y, NCO, N.sub.3, SiR.sub.3; or an optionally substituted group selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; [0163] where: [0164] two or more R.sup.c groups may be taken together with the carbon atoms to which they are attached and any intervening atoms to form one or more rings; [0165] when two R.sup.c groups are attached to the same carbon atom, they may be taken together along with the carbon atom to which they are attached to form a moiety selected from the group consisting of: a 3- to 8-membered spirocyclic ring, a carbonyl, an oxime, a hydrazone, an imine; [0166] R.sup.d is as defined above and described in classes and subclasses herein; [0167] Y is a divalent linker selected from the group consisting of: NR.sup.y, N(R)C(O), C(O)NR.sup.y, O, C(O), OC(O), C(O)O, S, SO, SO.sub.2, C(S), C(NR.sup.y), NN; a polyether; a C.sub.3 to C.sub.8 substituted or unsubstituted carbocycle; a 6- to 10-membered aryl; a 5- to 10-membered heteroaryl; and a 3- to 8-membered substituted or unsubstituted heterocycle; each m is independently 0 or an integer from 1 to 4, inclusive; [0168] q is 0 or an integer from 1 to 4, inclusive; and [0169] x is 0, 1, or 2.

[0170] In certain embodiments, a provided metal complex comprises at least one metal-coordinating moiety tethered to a carbon atom of only one phenyl ring of the salicylaldehyde-derived portion of a salen ligand, as shown in formula Ia:

##STR00074## [0171] wherein each of custom-character(Z).sub.b, M, R.sup.d, and a is as defined above and in the classes and subclasses herein, [0172] custom-character represents is an optionally substituted moiety linking the two nitrogen atoms of the diamine portion of the salen ligand, where custom-character is selected from the group consisting of a C.sub.3-C.sub.14 carbocycle, a C.sub.6-C.sub.10 aryl group, a C.sub.3-C.sub.14 heterocycle, and a C.sub.5-C.sub.10 heteroaryl group; or an optionally substituted C.sub.2-20 aliphatic group, wherein one or more methylene units are optionally and independently replaced by NR.sup.y, N(R.sup.y)C(O), C(O)N(R.sup.y), OC(O)N(R.sup.y), N(R.sup.y)C(O)O, OC(O)O, O, C(O), OC(O), C(O)O, S, SO, SO.sub.2, C(S), C(NR.sup.y), C(NOR.sup.y) or NN.

[0173] In certain embodiments, provided metal complexes of the present invention feature metal-coordinating moieties tethered to only one salicylaldehyde-derived portion of the salen ligand, while in other embodiments both salicylaldehyde-derived portions of the salen ligand bear one or more metal-coordinating moieties as in formula IIa:

##STR00075## [0174] where each of M, a, R.sup.d, custom-character, and custom-character(Z).sub.b are as defined above and in the classes and subclasses herein.

[0175] In certain embodiments of metal complexes having formulae Ia or IIa above, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the metal complex is independently selected from the group consisting of:

##STR00076## ##STR00077## ##STR00078## ##STR00079##

[0176] where custom-character(Z).sub.b represents one or more independently-defined metal-coordinating moieties which may be bonded to any one or more of the unsubstituted positions of the salicylaldehyde-derived phenyl ring.

[0177] In certain embodiments, there is a metal-coordinating moiety tethered to the position ortho to the metal-bound oxygen substituent of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand as in formulae IIIa and IIIb:

##STR00080## [0178] where each of M, a, R.sup.d, custom-character, and custom-character(Z).sub.b is as defined above, and in the classes and subclasses herein, and [0179] R.sup.2, R.sup.3, and R.sup.4, are independently at each occurrence selected from the group consisting of: hydrogen, halogen, NO.sub.2, CN, SR.sup.y, S(O)R.sup.y, S(O).sub.2R.sup.y, NR.sup.yC(O)R.sup.y, OC(O)R.sup.y, CO.sub.2R, NCO, N.sub.3, OR.sup.4, OC(O)N(R.sup.y).sub.2, N(R.sup.y).sub.2, NR.sup.yC(O)R.sup.y, NR.sup.yC(O)OR.sup.y; SiR.sub.3; or an optionally substituted group selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur, where two or more adjacent R groups can be taken together to form an optionally substituted saturated, partially unsaturated, or aromatic 5- to 12-membered ring containing 0 to 4 heteroatoms, where R.sup.y is as defined above.

[0180] In certain embodiments of metal complexes having formulae IIIa or IIIb, R.sup.2 and R.sup.4 are each hydrogen, and each R.sup.3 is, independently, H, or optionally substituted C.sub.1-C.sub.20 aliphatic.

[0181] In certain embodiments of metal complexes IIIa and IIIb, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the metal complex is independently selected from the group consisting of:

##STR00081## ##STR00082##

[0182] In other embodiments, there is a metal-coordinating moiety tethered to the position para to the phenolic oxygen of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand as in structures IVa and IVb:

##STR00083## [0183] where each R.sup.1 is independently selected from the group consisting of: hydrogen, halogen, NO.sub.2, CN, SR.sup.y, S(O)R.sup.y, S(O).sub.2R.sup.y, NR.sup.yC(O)R.sup.y, OC(O)R.sup.y, CO.sub.2R.sup.y, NCO, N.sub.3, OR.sup.y, OC(O)N(R.sup.y).sub.2, N(R.sup.y).sub.2, NR.sup.yC(O)R, NR.sup.yC(O)OR.sup.y; or an optionally substituted group selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur, where adjacent R.sup.1 and R.sup.2 groups can be taken together to form an optionally substituted saturated, partially unsaturated, or aromatic 5- to 12-membered ring containing 0 to 4 heteroatoms.

[0184] In certain embodiments of metal complexes having formulae IVa or IVb, R.sup.2 and R.sup.4 are hydrogen, and each R.sup.1 is, independently, optionally substituted C.sub.1-C.sub.20 aliphatic.

[0185] In certain embodiments of metal complexes IVa and IVb, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the metal complex is independently selected from the group consisting of:

##STR00084## ##STR00085##

[0186] In still other embodiments, there is a metal-coordinating moiety tethered to the position para to the imine substituent of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand as in formulae Va or Vb:

##STR00086## [0187] where M, a, R.sup.d, R.sup.1, R.sup.3, R.sup.4, custom-character, and custom-character(Z).sub.b are as defined above and in the classes and subclasses herein.

[0188] In certain embodiments of metal complexes having formulae Va or Vb, each R.sup.4 is hydrogen, and each R.sup.1 and R.sup.3 is, independently, hydrogen or optionally substituted C.sub.1-C.sub.20 aliphatic.

[0189] In certain embodiments of metal complexes Va and Vb, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the metal complex is independently selected from the group consisting of:

##STR00087## ##STR00088## ##STR00089##

[0190] In still other embodiments, there is a metal-coordinating moiety tethered to the position ortho to the imine substituent of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand as in formulae VIa and VIb:

##STR00090## [0191] where M, a, R.sup.d, R.sup.1, R.sup.2, R.sup.3, custom-character, and custom-character(Z).sub.b are as defined above and in the classes and subclasses herein.

[0192] In certain embodiments of metal complexes having formulae VIa or VIb, each R.sup.2 is hydrogen, and each R.sup.1 and R.sup.3 is, independently, hydrogen or optionally substituted C.sub.1-C.sub.20 aliphatic.

[0193] In certain embodiments of metal complexes VIa and VIb, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the metal complex is independently selected from the group consisting of:

##STR00091## ##STR00092## ##STR00093##

[0194] In still other embodiments, there are metal-coordinating moieties tethered to the position ortho to para to the phenolic oxygen of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand as in formulae VIIa and VIIb:

##STR00094## [0195] where each of M, a, R.sup.d, R.sup.2, R.sup.4, custom-character, and custom-charactern(Z).sub.b is as defined above and in the classes and subclasses herein.

[0196] In certain embodiments of compounds having formulae VIIa or VIIb, each R.sup.2 and R.sup.4, independently, hydrogen or optionally substituted C.sub.1-C.sub.20 aliphatic.

[0197] In certain embodiments of compounds having formulae VIIa or VIIb, each R.sup.2 and R.sup.4 is hydrogen.

[0198] In still other embodiments, there are metal-coordinating moieties tethered to the positions ortho and para to the imine substituent of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand as in formulae VIIIa and VIIIb:

##STR00095## [0199] where each of M, a, R.sup.d, R.sup.1, R.sup.3, custom-character and custom-character(Z).sub.b is as defined above and in the classes and subclasses herein.

[0200] In certain embodiments of metal complexes having formulae VIIIa or VIIIb, each R.sup.1 and R.sup.3 is, independently, optionally, hydrogen or substituted C.sub.1-C.sub.20 aliphatic.

[0201] In certain embodiments of the present invention, metal complexes of structures VIlla or VIIIb above, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the catalyst is independently selected from the group consisting of:

##STR00096## ##STR00097## ##STR00098## ##STR00099##

[0202] In yet other embodiments, there is a metal-coordinating moiety tethered to the imine carbon of the salen ligand as in formulae IXa and IXb:

##STR00100## [0203] where M, a, R.sup.1, R.sup.2, R.sup.3, R.sup.4, custom-character, and custom-character(Z).sub.b are as defined above with the proviso that the atom of the metal-coordinating moiety attached to the salen ligand is a carbon atom.

[0204] In certain embodiments of compounds having formulae IXa or IXb, each R.sup.2 and R.sup.4 is hydrogen, and each R.sup.1 and R.sup.3 is, independently, hydrogen or optionally substituted C.sub.1-C.sub.20 aliphatic.

[0205] In certain embodiments of the present invention, catalysts of structures IXa or IXb above, at least one of the phenyl rings comprising the salicylaldehyde-derived portion of the metal complex is independently selected from the group consisting of:

##STR00101## ##STR00102## ##STR00103##

[0206] As shown above, the two phenyl rings derived from salicylaldehyde in the core salen structures need not be the same. Though not explicitly shown in formulae Ia through IXb above, it is to be understood that a metal complex may have a metal-coordinating moiety attached to different positions on each of the two rings, and such metal complexes are specifically encompassed within the scope of the present invention. Furthermore, metal-coordinating moieties can be present on multiple parts of the ligand, for instance metal-coordinating moieties can be present on the diamine bridge and on one or both phenyl rings in the same metal complex.

[0207] In certain embodiments, the salen ligand cores of metal complexes Ia through IXb above are selected from the group shown below wherein any available position may be independently substituted with one or more R-groups or one or more metal-coordinating moieties as described above.

##STR00104##

[0208] where M, a, and custom-character(Z).sub.b are as defined above and in the classes and subclasses herein.

[0209] In another embodiment, at least one metal-coordinating moiety is tethered to the diamine-derived portion of the salen ligand, as shown in formula X:

##STR00105## [0210] where M, a, R.sup.d, R.sup.c, custom-character and custom-character(Z).sub.b are as defined above and in the classes and subclasses herein.

[0211] In certain embodiments, salen ligands of formula X are selected from an optionally substituted moiety consisting of:

##STR00106## ##STR00107## [0212] where M, a, R.sup.d, and custom-character(Z).sub.b are as defined above and in the classes and subclasses herein.

[0213] In certain embodiments, the diamine bridge of metal complexes of formula Xa an optionally substituted moiety selected from the group consisting of:

##STR00108## [0214] where each of M, a, and custom-character(Z).sub.b is as defined above and described in the classes and subclasses herein.

[0215] In certain embodiments, catalysts of the present invention comprise metal-tmtaa complexes. In certain embodiments, the moiety

##STR00109##

has the structure:

##STR00110##

where M, a and R.sup.d are as defined above and in the classes and subclasses herein, and [0216] R.sup.e at each occurrence is independently a metal-coordinating moiety (custom-character(Z).sub.b), hydrogen, halogen, OR, N(R.sub.2), SR, CN, NO.sub.2, SO.sub.2R, SOR, SO.sub.2N(R.sub.2); CNO, NRSO.sub.2R, NCO, N.sub.3, SiR.sub.3; or an optionally substituted group selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-2 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur.

##STR00111##

[0217] In certain embodiments, the moiety has the structure:

##STR00112## [0218] where each of M, a, R.sup.c, and R.sup.d is as defined above and in the classes and subclasses herein.

[0219] In certain embodiments, at least one metal-coordinating moiety is tethered to a diamine bridge of a ligand, as shown in formula III-a, III-b, and III-c:

##STR00113## [0220] wherein each of R.sup.c, R.sup.d, R.sup.e, Z, b, a, M.sup.1, and M.sup.2, is independently as defined above the described in classes and subclasses herein, and [0221] R.sup.12 is optionally present, and if present is selected from the group consisting of: a custom-character(Z).sub.b group; or an optionally substituted radical selected from the group consisting of C.sub.1-20 aliphatic; C.sub.1-20 heteroaliphatic; and phenyl.

[0222] In certain embodiments, at least one metal-coordinating moiety is tethered to a diamine bridge of a ligand, as shown in formula IV-a, IV-b, and IV-c:

##STR00114## [0223] wherein each of R.sup.c, R.sup.d, R.sup.e, Z, b, a, M.sup.1, M.sup.2, and R.sup.12 is independently as defined above the described in classes and subclasses herein.

[0224] In certain embodiments, at least one metal-coordinating moiety is tethered to a cyclic diamine bridge of a ligand, as shown in formula V-a, V-b, and V-c:

##STR00115## [0225] wherein each of R.sup.e, R.sup.d, R.sup.e, Z, b, a, M.sup.1, M.sup.2, and R.sup.12 is independently as defined above the described in classes and subclasses herein.

[0226] In certain embodiments, at least one metal-coordinating moiety is tethered to a cyclic diamine bridge of a ligand, as shown in formula VI-a, VI-b, and VI-c:

##STR00116## [0227] wherein each of R.sup.c, R.sup.d, R.sup.e, Z, b, a, M.sup.1, M.sup.2, and R.sup.2 is independently as defined above the described in classes and subclasses herein.

[0228] In certain embodiments, catalysts of the present invention comprise ligands capable of coordinating two metal atoms.

##STR00117## [0229] wherein each of R.sup.d, R.sup.e, M.sup.1, M.sup.2, b, a, and custom-character(Z).sub.b is independently as defined above and described in classes and subclasses herein.
IIb. Metal Atoms in the Acidic Metal Complexes

[0230] In certain embodiments, the metal atom M in any of the Lewis acidic metal complexes described above and in the classes, subclasses and tables herein, is selected from the periodic table groups 2-13, inclusive. In certain embodiments, M is a transition metal selected from the periodic table groups 4, 6, 11, 12 and 13. In certain embodiments, M is aluminum, chromium, titanium, indium, gallium, zinc cobalt, or copper. In certain embodiments, M is aluminum. In other embodiments, M is chromium.

[0231] In certain embodiments, M has an oxidation state of +2. In certain embodiments, M is Zn(II), Cu(II), Mn(II), Co(II), Ru(II), Fe(II), Co(II), Rh(II), Ni(II), Pd(II) or Mg(II). In certain embodiments M is Zn(II). In certain embodiments M is Cu(II).

[0232] In certain embodiments, M has an oxidation state of +3. In certain embodiments, M is Al(III), Cr(III), Fe(III), Co(III), Ti(III) In(III), Ga(III) or Mn(III). In certain embodiments M is Al(III). In certain embodiments M is Cr(III).

[0233] In certain embodiments, M has an oxidation state of +4. In certain embodiments, M is Ti(IV) or Cr(IV).

[0234] In certain embodiments, M.sup.1 and M.sup.2 are each independently a metal atom selected from the periodic table groups 2-13, inclusive. In certain embodiments, each M.sup.1 and M.sup.2 is a transition metal selected from the periodic table groups 4, 6, 11, 12 and 13. In certain embodiments, M.sup.1 and M.sup.2 are selected from aluminum, chromium, titanium, indium, gallium, zinc cobalt, or copper. In certain embodiments, M.sup.1 and M.sup.2 are aluminum. In other embodiments, M.sup.1 and M.sup.2 are chromium. In certain embodiments, M.sup.1 and M.sup.2 are the same. In certain embodiments, M.sup.1 and M.sup.2 are the same metal, but have different oxidation states. In certain embodiments, M.sup.1 and M.sup.2 are different metals.

[0235] In certain embodiments, one or more of M.sup.1 and M.sup.2 has an oxidation state of +2. In certain embodiments, M.sup.1 is Zn(II), Cu(II), Mn(II), Co(II), Ru(II), Fe(II), Co(II), Rh(II), Ni(II), Pd(II) or Mg(II). In certain embodiments M.sup.1 is Zn(II). In certain embodiments M.sup.1 is Cu(II). In certain embodiments, M.sup.2 is Zn(II), Cu(II), Mn(II), Co(II), Ru(II), Fe(II), Co(II), Rh(II), Ni(II), Pd(II) or Mg(II). In certain embodiments M.sup.2 is Zn(II). In certain embodiments M.sup.2 is Cu(II).

[0236] In certain embodiments, one or more of M.sup.1 and M.sup.2 has an oxidation state of +3. In certain embodiments, M.sup.1 is Al(III), Cr(III), Fe(III), Co(III), Ti(III) In(III), Ga(III) or Mn(III). In certain embodiments M.sup.1 is Al(III). In certain embodiments M.sup.1 is Cr(III). In certain embodiments, M.sup.2 is Al(III), Cr(III), Fe(III), Co(III), Ti(III) In(III), Ga(III) or Mn(III). In certain embodiments M.sup.2 is Al(III). In certain embodiments M.sup.2 is Cr(III).

[0237] In certain embodiments, one or more of M.sup.1 and M.sup.2 has an oxidation state of +4. In certain embodiments, M.sup.1 is Ti(IV) or Cr(IV). In certain embodiments, M.sup.2 is Ti(IV) or Cr(IV).

[0238] In certain embodiments, one or more neutral two electron donors coordinate to M M.sup.1 or M.sup.2 and fill the coordination valence of the metal atom. In certain embodiments, the neutral two electron donor is a solvent molecule. In certain embodiments, the neutral two electron donor is an ether. In certain embodiments, the neutral two electron donor is tetrahydrofuran, diethyl ether, acetonitrile, carbon disulfide, or pyridine. In certain embodiments, the neutral two electron donor is tetrahydrofuran. In certain embodiments, the neutral two electron donor is an epoxide. In certain embodiments, the neutral two electron donor is an ester or a lactone.

III. The Metal Carbonyl Component

[0239] As noted above, catalysts of the present invention comprise at least one metal carbonyl compound. Typically, a single metal carbonyl compound is provided, but in certain embodiments mixtures of two or more metal carbonyl compounds are provided. (Thus, when a provided metal carbonyl compound comprises, e.g., a neutral metal carbonyl compound, it is understood that the provided metal carbonyl compound can be a single neutral metal carbonyl compound, or a neutral metal carbonyl compound in combination with one or more other metal carbonyl compounds.) Preferably, the provided metal carbonyl compound is capable of ring-opening an epoxide and facilitating the insertion of CO into the resulting metal carbon bond. Metal carbonyl compounds with this reactivity are well known in the art and are used for laboratory experimentation as well as in industrial processes such as hydroformylation.

[0240] In certain embodiments, a provided metal carbonyl compound comprises an anionic metal carbonyl moiety. In other embodiments, a provided metal carbonyl compound comprises a neutral metal carbonyl compound. In certain embodiments, a provided metal carbonyl compound comprises a metal carbonyl hydride or a hydrido metal carbonyl compound. In some embodiments, a provided metal carbonyl compound acts as a pre-catalyst which reacts in situ with one or more other components to provide an active species different from the compound initially provided. Such pre-catalysts are specifically encompassed by the present invention as it is recognized that the active species in a given reaction may not be known with certainty; thus the identification of such a reactive species in situ does not itself depart from the spirit or teachings of the present invention.

[0241] In certain embodiments, the metal carbonyl compound comprises an anionic metal carbonyl species. In certain embodiments, such anionic metal carbonyl species have the general formula [Q.sub.dM.sub.e(CO).sub.w].sup.y, where Q is any ligand and need not be present, M is a metal atom, d is an integer between 0 and 8 inclusive, e is an integer between 1 and 6 inclusive, w is a number such as to provide the stable anionic metal carbonyl complex, and y is the charge of the anionic metal carbonyl species. In certain embodiments, the anionic metal carbonyl has the general formula [QM(CO).sub.w].sup.y, where Q is any ligand and need not be present, M is a metal atom, w is a number such as to provide the stable anionic metal carbonyl, and y is the charge of the anionic metal carbonyl.

[0242] In certain embodiments, the anionic metal carbonyl species include monoanionic carbonyl complexes of metals from groups 5, 7, or 9 of the periodic table or dianionic carbonyl complexes of metals from groups 4 or 8 of the periodic table. In some embodiments, the anionic metal carbonyl compound contains cobalt or manganese. In some embodiments, the anionic metal carbonyl compound contains rhodium. Suitable anionic metal carbonyl compounds include, but are not limited to: [Co(CO).sub.4], [Ti(CO).sub.6].sup.2, [V(CO).sub.6].sup., [Rh(CO).sub.4].sup., [Fe(CO).sub.4].sup.2, [Ru(CO).sub.4].sup.2, [Os(CO).sub.4].sup.2, [Cr.sub.2(CO).sub.10].sup.2, [Fe.sub.2(CO).sub.8].sup.2, [Tc(CO).sub.5].sup., [Re(CO).sub.5].sup., [Mn(CO).sub.5].sup., or combinations thereof. In certain embodiments, the anionic metal carbonyl comprises [Co(CO).sub.4].sup.. In some embodiments, a mixture of two or more anionic metal carbonyl complexes may be present in the polymerization system.

[0243] The term such as to provide a stable anionic metal carbonyl for [Q.sub.dM.sub.e(CO).sub.w].sup.y is used herein to mean that [Q.sub.dM.sub.e(CO).sub.w].sup.y is a species characterizable by analytical means, e.g., NMR, IR, X-ray crystallography, Raman spectroscopy and/or electron spin resonance (EPR) and isolable in catalyst form in the presence of a suitable cation or a species formed in situ. It is to be understood that metals which can form stable metal carbonyl complexes have known coordinative capacities and propensities to form polynuclear complexes which, together with the number and character of optional ligands Q that may be present and the charge on the complex will determine the number of sites available for CO to coordinate and therefore the value of w. Typically, such compounds conform to the 18-electron rule. Such knowledge is within the grasp of one having ordinary skill in the arts pertaining to the synthesis and characterization of metal carbonyl compounds.

[0244] In embodiments where the provided metal carbonyl compound is an anionic species, one or more cations must also necessarily be present. The present invention places no particular constraints on the identity of such cations. In certain embodiments, the cation associated with an anionic metal carbonyl compound comprises a reaction component of another category described hereinbelow. For example, in certain embodiments, the metal carbonyl anion is associated with a Lewis acidic metal complex as described above wherein the metal complex has a net positive charge. In other embodiments a cation associated with a provided anionic metal carbonyl compound is a simple metal cation such as those from Groups 1 or 2 of the periodic table (e.g. Na.sup.+, Li.sup.+, K.sup.+, Mg.sup.2+ and the like). In other embodiments a cation associated with a provided anionic metal carbonyl compound is a bulky non electrophilic cation such as an onium salt (e.g. Bu.sub.4N+, PPN.sup.+, Ph.sub.4P Ph.sub.4As.sup.+, and the like). In other embodiments, a metal carbonyl anion is associated with a protonated nitrogen compound, (e.g. a cation may comprise a compound such as MeTBD-H.sup.+, DMAP-H.sup.+, DABCO-H.sup.+, DBU-H.sup.+ and the like).

[0245] In certain embodiments, a provided metal carbonyl compound comprises a neutral metal carbonyl. In certain embodiments, such neutral metal carbonyl compounds have the general formula Q.sub.dM.sub.e(CO).sub.w, where Q is any ligand and need not be present, M is a metal atom, d is an integer between 0 and 8 inclusive, e is an integer between 1 and 6 inclusive, and w is a number such as to provide the stable neutral metal carbonyl complex. In certain embodiments, the neutral metal carbonyl has the general formula QM(CO).sub.w. In certain embodiments, the neutral metal carbonyl has the general formula M(CO).sub.w. In certain embodiments, the neutral metal carbonyl has the general formula QM.sub.2(CO).sub.w. In certain embodiments, the neutral metal carbonyl has the general formula M.sub.2(CO).sub.w. Suitable neutral metal carbonyl compounds include, but are not limited to: Ti(CO).sub.7, V.sub.2(CO).sub.12, Cr(CO).sub.6, Mo(CO).sub.6, W(CO).sub.6, Mn.sub.2(CO).sub.10, Tc.sub.2(CO).sub.10, Re.sub.2(CO).sub.10, Fe(CO).sub.5, Ru(CO).sub.5, Os(CO).sub.5, Ru.sub.3(CO).sub.12, Os.sub.3(CO).sub.12, Fe.sub.3(CO).sub.12, Fe.sub.2(CO).sub.9, Co.sub.4(CO).sub.12, Rh.sub.4(CO).sub.12, Rh.sub.6(CO).sub.16, Ir.sub.4(CO).sub.12, Co.sub.2(CO).sub.8, Ni(CO).sub.4, or a combination thereof.

[0246] The term such as to provide a stable neutral metal carbonyl for Q.sub.dM.sub.e(CO).sub.w, is used herein to mean that Q.sub.dM.sub.e(CO).sub.w, is a species characterizable by analytical means, e.g., NMR, IR, X-ray crystallography, Raman spectroscopy and/or electron spin resonance (EPR) and isolable in pure form or a species formed in situ. It is to be understood that metals which can form stable metal carbonyl complexes have known coordinative capacities and propensities to form polynuclear complexes which, together with the number and character of optional ligands Q that may be present will determine the number of sites available for CO to coordinate and therefore the value of w. Typically, such compounds conform to stoichiometries conforming to the 18-electron rule. Such knowledge is within the grasp of one having ordinary skill in the arts pertaining to the synthesis and characterization of metal carbonyl compounds.

[0247] In certain embodiments, one or more of the CO ligands of any of the metal carbonyl compounds described above is replaced with a ligand Q. In certain embodiments, Q is a phosphine ligand. In certain embodiments, Q is a triaryl phosphine. In certain embodiments, Q is trialkyl phosphine. In certain embodiments, Q is a phosphite ligand. In certain embodiments, Q is an optionally substituted cyclopentadienyl ligand. In certain embodiments, Q is cp. In certain embodiments, Q is cp*.

[0248] In certain embodiments, catalysts of the present invention comprise hydrido metal carbonyl compounds. In certain embodiments, such compounds are provided as the hydrido metal carbonyl compound, while in other embodiments, the hydrido metal carbonyl is generated in situ by reaction with hydrogen gas, or with a protic acid using methods known in the art (see for example Chem. Rev., 1972, 72 (3), pp 231-281 DOI: 10.1021/cr60277a003, the entirety of which is incorporated herein by reference).

[0249] In certain embodiments, the hydrido metal carbonyl (either as provided or generated in situ) comprises one or more of HCo(CO).sub.4, HCoQ(CO).sub.3, HMn(CO).sub.5, HMn(CO).sub.4Q, HW(CO).sub.3Q, HRe(CO).sub.5, HMo(CO).sub.3Q, HOs(CO).sub.2Q, HMo(CO).sub.2Q.sub.2, HFe(CO.sub.2)Q, HW(CO).sub.2Q.sub.2, HRuCOQ.sub.2, H.sub.2Fe(CO).sub.4, or H.sub.2Ru(CO).sub.4, where each Q is independently as defined above and in the classes and subclasses herein. In certain embodiments, the metal carbonyl hydride (either as provided or generated in situ) comprises HCo(CO).sub.4. In certain embodiments, the metal carbonyl hydride (either as provided or generated in situ) comprises HCo(CO).sub.3PR.sub.3, where each R is independently an optionally substituted aryl group, an optionally substituted C.sub.1-20 aliphatic group, an optionally substituted C.sub.1-10 alkoxy group, or an optionally substituted phenoxy group. In certain embodiments, the metal carbonyl hydride (either as provided or generated in situ) comprises HCo(CO).sub.3cp, where cp represents an optionally substituted pentadienyl ligand. In certain embodiments, the metal carbonyl hydride (either as provided or generated in situ) comprises HMn(CO).sub.5. In certain embodiments, the metal carbonyl hydride (either as provided or generated in situ) comprises H.sub.2Fe(CO).sub.4.

[0250] In certain embodiments, for any of the metal carbonyl compounds described above, M comprises a transition metal. In certain embodiments, for any of the metal carbonyl compounds described above, M is selected from Groups 5 (Ti) to 10 (Ni) of the periodic table. In certain embodiments, M is a Group 9 metal. In certain embodiments, M is Co. In certain embodiments, M is Rh. In certain embodiments, M is Ir. In certain embodiments, M is Fe. In certain embodiments, M is Mn.

[0251] In certain embodiments, one or more ligands Q is present in a provided metal carbonyl compound. In certain embodiments, Q is a phosphine ligand. In certain embodiments, Q is a triaryl phosphine. In certain embodiments, Q is trialkyl phosphine. In certain embodiments, Q is a phosphite ligand. In certain embodiments, Q is an optionally substituted cyclopentadienyl ligand. In certain embodiments, Q is cp. In certain embodiments, Q is cp*.

[0252] In certain embodiments, the anionic metal carbonyl compound has the general formula [Q.sub.dM.sub.e(CO).sub.w]Y, where Q is any ligand and need not be present, M is a metal atom, d is an integer between 0 and 8 inclusive, e is an integer between 1 and 6 inclusive, w is a number such as to provide the stable anionic metal carbonyl complex, and x is the charge of the anionic metal carbonyl compound. In certain embodiments, the anionic metal carbonyl has the general formula [QM(CO).sub.w].sup.y, where Q is any ligand and need not be present, M is a metal atom, w is a number such as to provide the stable anionic metal carbonyl, and y is the charge of the anionic metal carbonyl.

[0253] In certain embodiments, the anionic metal carbonyl compounds include monoanionic carbonyl complexes of metals from groups 5, 7, or 9 of the periodic table and dianionic carbonyl complexes of metals from groups 4 or 8 of the periodic table. In some embodiments, the anionic metal carbonyl compound contains cobalt or manganese. In some embodiments, the anionic metal carbonyl compound contains rhodium. Suitable anionic metal carbonyl compounds include, but are not limited to: [Co(CO).sub.4].sup., [Ti(CO).sub.6].sup.2, [V(CO).sub.6].sup., [Rh(CO).sub.4].sup., [Fe(CO).sub.4].sup.2, [Ru(CO).sub.4].sup.2, [Os(CO).sub.4].sup.2, [Cr.sub.2(CO).sub.10].sup.2, [Fe.sub.2(CO).sub.8].sup.2, [Tc(CO).sub.5].sup., [Re(CO).sub.5], [Mn(CO).sub.5], or combinations thereof. In certain embodiments, the anionic metal carbonyl is [Co(CO).sub.4].sup.. In some cases, a mixture of two or more anionic metal carbonyl complexes may be present in the catalyst.

[0254] The term such as to provide a stable anionic metal carbonyl for [Q.sub.dM.sub.e(CO).sub.w].sup.y is used herein to mean that [Q.sub.dM.sub.e(CO).sub.w].sup.y is a species characterizable by analytical means, e.g., NMR, IR, X-ray crystrallography, Raman spectroscopy and/or electron spin resonance (EPR) and isolable in catalyst form as the anion for a metal complex cation or a species formed in situ.

[0255] In certain embodiments, one or two of the CO ligands of any of the metal carbonyl compounds described above is replaced with a ligand Q. In certain embodiments, the ligand Q is present and represents a phosphine ligand. In certain embodiments, Q is present and represents a cyclopentadienyl (cp) ligand.

IV. Carbonylation Catalysts

[0256] In certain embodiments, catalysts of the present invention include the combination of: [0257] i) one or more metal-coordinating moieties, where each metal-coordinating moiety comprises the combination of a linker as defined in Section Ia above and 1 to 4 metal-coordinating groups as defined in Section Ib above; [0258] ii) one or more ligands as defined in Section IIa to which at least one metal-coordinating moiety is covalently tethered and the ligand(s) is/are coordinated to one or two metal atoms as described in Section IIb to form a Lewis acidic metal complex; and [0259] iii) at least one metal carbonyl species as described in Section III.

[0260] In certain embodiments, catalysts of the present invention include the combination of: [0261] i) a Lewis acidic metal complex comprising one or two metal atoms coordinated to at least one ligand said ligand bearing at least one covalently tethered metal-coordinating moiety of formula custom-character(Z).sub.b, [0262] where, custom-character is selected from the group consisting of:

##STR00118## ##STR00119## [0263] where R.sup.y is as defined above and described in classes and subclasses herein, and each s is independently 0-6, t is 0-4, * represents the site of attachment to a ligand, and each # represents a site of attachment of a metal-coordinating group Z, and [0264] each Z is independently selected from a neutral nitrogen-containing functional group, a neutral nitrogen-containing heterocycle or heteroaryl, a phosphorous-containing functional group and a boron containing functional group; [0265] and, [0266] ii) an anionic metal carbonyl compound of formula [Q.sub.dM.sub.e(CO).sub.w].sup.y, [0267] where Q is any ligand and need not be present, [0268] M is a metal atom, [0269] d is an integer between 0 and 8 inclusive, [0270] e is an integer between 1 and 6 inclusive, [0271] w is a number such as to provide the stable anionic metal carbonyl complex, and [0272] y is the charge of the anionic metal carbonyl species.

[0273] In certain embodiments, catalysts of the present invention include the combination of: [0274] a metal carbonyl compound, and [0275] a Lewis acidic metal complex selected from Table A1, where Z and M are as defined above and in the classes and subclasses herein:

TABLE-US-00002 TABLE A1 [00120]embedded image [00121]embedded image [00122]embedded image [00123]embedded image [00124]embedded image [00125]embedded image [00126]embedded image [00127]embedded image [00128]embedded image [00129]embedded image [00130]embedded image [00131]embedded image [00132]embedded image [00133]embedded image [00134]embedded image [00135]embedded image [00136]embedded image [00137]embedded image [00138]embedded image [00139]embedded image [00140]embedded image [00141]embedded image [00142]embedded image [00143]embedded image [00144]embedded image [00145]embedded image [00146]embedded image

[0276] In certain embodiments, each occurrence of M in any complex in Table A1 comprises a moiety:

##STR00147##

[0277] In certain embodiments, each occurrence of M in any complex in Table A1 comprises a moiety:

##STR00148##

[0278] In certain embodiments, each occurrence of M in any complex in Table A1 comprises a moiety:

##STR00149##

[0279] In certain embodiments, each occurrence of M in any complex in Table A1 comprises a moiety:

##STR00150##

[0280] In certain embodiments, each occurrence of M in any complex in Table A1 comprises a moiety:

##STR00151##

[0281] In certain embodiments, for catalysts of Table A1, (Z) comprises a neutral nitrogen-containing functional group. In certain embodiments, for catalysts of Table A1, (Z) comprises a neutral phosphorous-containing functional group. In certain embodiments, for catalysts of Table A1, (Z) comprises a neutral boron-containing functional group. In certain embodiments, for catalysts of Table A1, (Z) comprises a neutral nitrogen-containing heterocycle or heteroaryl. In certain embodiments, for catalysts of Table A1, (Z) comprises a phosphine. In certain embodiments, for catalysts of Table A1, (Z) comprises a phosphite. In certain embodiments, for catalysts of Table A1, (Z) comprises a nitrile.

[0282] In certain embodiments, catalysts of the present invention include the combination of: [0283] a metal carbonyl compound, and [0284] a Lewis acidic metal complex selected from Table A2, where Z and each M is independently as defined above and in the classes and subclasses herein:

TABLE-US-00003 TABLE A2 [00152]embedded image [00153]embedded image [00154]embedded image [00155]embedded image [00156]embedded image [00157]embedded image [00158]embedded image [00159]embedded image [00160]embedded image [00161]embedded image [00162]embedded image [00163]embedded image [00164]embedded image [00165]embedded image [00166]embedded image [00167]embedded image [00168]embedded image [00169]embedded image [00170]embedded image [00171]embedded image [00172]embedded image [00173]embedded image [00174]embedded image [00175]embedded image [00176]embedded image [00177]embedded image [00178]embedded image

[0285] In certain embodiments, each occurrence of M in any complex in Table A2 comprises a moiety:

##STR00179##

[0286] In certain embodiments, each occurrence of M in any complex in Table A2 comprises a moiety:

##STR00180##

[0287] In certain embodiments, each occurrence of M in any complex in Table A2 comprises a moiety:

##STR00181##

[0288] In certain embodiments, each occurrence of M in any complex in Table A2 comprises a moiety:

##STR00182##

[0289] In certain embodiments, each occurrence of M in any complex in Table A2 comprises a moiety:

##STR00183##

[0290] In certain embodiments, for catalysts of Table A2, (Z) comprises a neutral nitrogen-containing functional group. In certain embodiments, for catalysts of Table A2, (Z) comprises a neutral phosphorous-containing functional group. In certain embodiments, for catalysts of Table A2, (Z) comprises a neutral boron-containing functional group. In certain embodiments, for catalysts of Table A2, (Z) comprises a neutral nitrogen-containing heterocycle or heteroaryl. In certain embodiments, for catalysts of Table A2, (Z) comprises a phosphine. In certain embodiments, for catalysts of Table A2, (Z) comprises a phosphite. In certain embodiments, for catalysts of Table A2, (Z) comprises a nitrile.

[0291] In certain embodiments, catalysts of the present invention include a Lewis Acidic metal complex chosen from Catalyst Table 1:

TABLE-US-00004 CATALYST TABLE 1 [00184]embedded image [00185]embedded image [00186]embedded image [00187]embedded image [00188]embedded image [00189]embedded image [00190]embedded image [00191]embedded image [00192]embedded image [00193]embedded image [00194]embedded image [00195]embedded image [00196]embedded image [00197]embedded image [00198]embedded image

[0292] In certain embodiments, catalysts of the present invention include a complex chosen from Catalyst Table 2:

TABLE-US-00005 CATALYST TABLE 2 [00199]embedded image [00200]embedded image [00201]embedded image [00202]embedded image [00203]embedded image [00204]embedded image [00205]embedded image [00206]embedded image [00207]embedded image [00208]embedded image [00209]embedded image [00210]embedded image [00211]embedded image [00212]embedded image [00213]embedded image [00214]embedded image [00215]embedded image [00216]embedded image [00217]embedded image [00218]embedded image [00219]embedded image [00220]embedded image [00221]embedded image [00222]embedded image [00223]embedded image [00224]embedded image [00225]embedded image [00226]embedded image [00227]embedded image [00228]embedded image [00229]embedded image [00230]embedded image [00231]embedded image [00232]embedded image [00233]embedded image [00234]embedded image [00235]embedded image [00236]embedded image [00237]embedded image [00238]embedded image [00239]embedded image [00240]embedded image [00241]embedded image [00242]embedded image [00243]embedded image [00244]embedded image [00245]embedded image [00246]embedded image

[0293] In certain embodiments, catalysts of the present invention include a complex chosen from Catalyst Table 3:

TABLE-US-00006 CATALYST TABLE 3 [00247]embedded image [00248]embedded image [00249]embedded image [00250]embedded image [00251]embedded image [00252]embedded image [00253]embedded image [00254]embedded image [00255]embedded image [00256]embedded image [00257]embedded image [00258]embedded image [00259]embedded image [00260]embedded image [00261]embedded image [00262]embedded image [00263]embedded image [00264]embedded image [00265]embedded image [00266]embedded image [00267]embedded image [00268]embedded image [00269]embedded image [00270]embedded image [00271]embedded image [00272]embedded image [00273]embedded image [00274]embedded image [00275]embedded image [00276]embedded image [00277]embedded image [00278]embedded image [00279]embedded image [00280]embedded image [00281]embedded image [00282]embedded image [00283]embedded image [00284]embedded image [00285]embedded image [00286]embedded image [00287]embedded image [00288]embedded image [00289]embedded image [00290]embedded image [00291]embedded image [00292]embedded image [00293]embedded image [00294]embedded image [00295]embedded image [00296]embedded image [00297]embedded image

[0294] In certain embodiments, each occurrence of M in any compound of Catalyst Tables 1-3 comprises a moiety:

##STR00298##

[0295] In certain embodiments, each occurrence of M in any compound of Catalyst Tables 1-3 comprises a moiety:

##STR00299##

[0296] In certain embodiments, each occurrence of M in any compound of Catalyst Tables 1-3 comprises a moiety:

##STR00300##

[0297] In certain embodiments, each occurrence of M in any compound of Catalyst Tables 1-3 comprises a moiety:

##STR00301##

[0298] In certain embodiments, each occurrence of M in any compound of Catalyst Tables 1-3 comprises a moiety:

##STR00302##

[0299] While not depicted, it will be appreciated that a tetracarbonyl cobaltate anion as shown above can be associated with any of the compounds in Table A1, Table A2 or in Catalyst Tables 1-3, and the present invention encompasses such complexes.

[0300] In certain embodiments, tetracarbonyl cobaltate anions associated with any of the compounds in Table A1, Table A2 or in Catalyst Tables 1-3 are replaced by [Rh(CO).sub.4].sup.. In certain embodiments, tetracarbonyl cobaltate anions associated with any of the compounds in Catalyst Tables 1-3 are replaced by [Fe(CO).sub.5].sup.2. In certain embodiments, tetracarbonyl cobaltate anions associated with any of the compounds in Catalyst Tables 1-3 are replaced by [Mn(CO).sub.5].sup..

[0301] In another aspect, the present invention encompasses compositions of matter arising from any of the Lewis acidic metal complexes described above when a metal carbonyl is associated with one or more of the metal-coordinating groups tethered to the complex. In certain embodiments, such compounds arise from the interaction of a metal carbonyl compound of formula [Q.sub.dM.sub.e(CO).sub.w].sup.y with a Z group on the Lewis acidic metal complex to produce a new metal carbonyl species having a formula [Z.sub.fQ.sub.dM.sub.e(CO).sub.w].sup.y where Q, M, e, d, w, and y are as defined above and in the classes and subclasses herein and f is an integer representing the number of coordination sites occupied by the Z group or groups present in the new metal carbonyl complexfor clarity, it is meant to be understood here that f may be equal to the number of Z groups coordinated with the metal or metals in the new complex (for example when Z is a monodentate coordinating group) or f may be lesser than the number of Z groups present if one or more Z groups is a polydentate coordinating group. The variables d and w in the product metal carbonyl compound have the same meanings as d and w in the starting metal carbonyl compound, but the sum of d and w will be reduced relative to d and w because of the presence of one or more Z groups in the new metal carbonyl compound. In certain embodiments, the sum of f, d, and w and is equal to the sum of d and w. In certain embodiments, d is equal to d and f is equal to w minus w.

[0302] In certain embodiments, the present invention encompasses compositions of matter comprising compounds of formula: [Z:Co(CO).sub.3].sup. where Z is selected from any of the metal-coordinating groups described above and in the classes and subclasses herein, : represents a non-covalent coordinative bond between a lone pair of electrons on a heteroatom in the Z group and where Z is covalently tethered to a ligand of a Lewis-acidic metal complex as described above.

[0303] In certain embodiments, the present invention encompasses compositions of matter comprising compounds of formula: [Z:Co.sub.2(CO).sub.7] where Z is selected from any of the metal-coordinating groups described above and in the classes and subclasses herein, : represents a non-covalent coordinative bond between a lone pair of electrons on a heteroatom in the Z group and where Z is covalently tethered to a ligand of a Lewis-acidic metal complex as described above.

[0304] In certain embodiments, the present invention encompasses compositions of matter comprising compounds of formula: [Z:Rh(CO).sub.3].sup. where Z is selected from any of the metal-coordinating groups described above and in the classes and subclasses herein, : represents a non-covalent coordinative bond between a lone pair of electrons on a heteroatom in the Z group and where Z is covalently tethered to a ligand of a Lewis-acidic metal complex as described above.

[0305] In certain embodiments, the present invention encompasses compositions of matter comprising compounds of formula: [(Z:).sub.2Co(CO).sub.2].sup. where each Z is independently selected from any of the metal-coordinating groups described above and in the classes and subclasses herein, each : represents a non-covalent coordinative bond between a lone pair of electrons on a heteroatom in the Z group where each Z is covalently tethered to the ligand of a Lewis-acidic metal complex as described above. In this case, the two Z groups may be attached to the same metal complex, or each may be tethered to a separate metal complex.

[0306] In certain embodiments, the present invention encompasses compositions of matter comprising compounds of formula: [Z:Co.sub.2(CO).sub.7] where Z is selected from any of the metal-coordinating groups described above and in the classes and subclasses herein, : represents a non-covalent coordinative bond between a lone pair of electrons on a heteroatom in the Z group and where Z is covalently tethered to a ligand of a Lewis-acidic metal complex as described above.

[0307] In certain embodiments, the present invention encompasses compositions of matter comprising compounds of formula: [(Z:).sub.2Co(CO).sub.6] where each Z is independently selected from any of the metal-coordinating groups described above and in the classes and subclasses herein, each : represents a non-covalent coordinative bond between a lone pair of electrons on a heteroatom in the Z group where each Z is covalently tethered to the ligand of a Lewis-acidic metal complex as described above. In this case, the two Z groups may be attached to the same metal complex, or each may be tethered to a separate metal complex.

[0308] To further clarify what is meant by the description above and avoid ambiguity, the scheme below shows a composition arising from the combination of a chromium-based Lewis acidic metal complex (bearing a metal-coordinating group PPh.sub.2 according to the present invention) and the metal carbonyl compound tetracarbonyl cobaltate. The resulting coordination compound arising from the displacement of one CO ligand on the cobalt atom by the phosphine group on the Lewis acidic metal complex is depicted as compound E-1.

##STR00303##

[0309] E-1 thus corresponds to a composition [Z.sub.fQ.sub.dM.sub.e(CO).sub.w].sup.y where Z is the PPh.sub.2 group and the metal complex to which it is covalently tethered, Q is absent (i.e. d is 0), M is Co, e is 1, w is 3, and y is 1. In this case, the sum of d and w in the starting metal carbonyl compound (0+4) equals the sum of f, d, and w in E-1 (1+0+3). Corresponding compositions arising from any of the Lewis acidic metal complexes described herein in combination any of the metal carbonyl compounds described are encompassed by the present invention.

VI. Carbonylation Methods

[0310] In another aspect, the present invention provides methods of carbonylating heterocycles using the catalysts disclosed hereinabove. In certain embodiments, the invention encompasses a method comprising the steps: [0311] a) providing a compound having formula:

##STR00304## [0312] wherein: [0313] R.sup.a is hydrogen or an optionally substituted group selected from the group consisting of C.sub.1-30 aliphatic; C.sub.1-30 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-3 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; [0314] each of R.sup.b, R.sup.c, and R.sup.d is independently hydrogen or an optionally substituted group selected from the group consisting of C.sub.1-12 aliphatic; C.sub.1-12 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-3 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; [0315] wherein any of (R.sup.b and R.sup.c), (R.sup.d and R.sup.d), and (R.sup.a and R.sup.b) can be taken together with their intervening atoms to form one or more rings selected from the group consisting of: optionally substituted C.sub.3-C.sub.14 carbocycle, optionally substituted C.sub.3-C.sub.14 heterocycle, optionally substituted C.sub.6-C.sub.10 aryl, and optionally substituted C.sub.5-C.sub.10 heteroaryl; [0316] X is selected from the group consisting of O, S, and NR.sup.e where R.sup.e is selected from the group consisting of hydrogen or an optionally substituted group selected from the group consisting of C.sub.1-30 aliphatic; C.sub.1-30 heteroaliphatic having 1-4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; 6- to 10-membered aryl; 5- to 10-membered heteroaryl having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and 4- to 7-membered heterocyclic having 1-3 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur; [0317] n is 0 or 1; and [0318] Y is CO or CH.sub.2; [0319] b) contacting the compound having the formula (1) and carbon monoxide in the presence of a catalyst described above, to provide a product having formula:

##STR00305## [0320] where R.sup.a, R.sup.b, R.sup.e, R.sup.d, and X, correspond to R.sup.a, R.sup.b, R.sup.e, R.sup.d, and X, in (1) including R.sup.b and R.sup.c forming a ring if that is the case for (1); and in the case where n for (1) is 0, n for (2) is 0 or 1, and in the case where n for (1) is 1, n for (2) is 1.

[0321] In certain embodiments of the carbonylation method described above, n for (1) is 0 so that the formula for (1) becomes:

##STR00306##

and the product has the formula:

##STR00307##

[0322] In certain embodiments of the carbonylation method described above, X for (3) is oxygen so that compound is an epoxide and the formula for (3) becomes:

##STR00308##

and the product has the formula:

##STR00309##

[0323] In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, and R.sup.c are H, and R.sup.d comprises an optionally substituted C.sub.1-20 aliphatic group. In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, R.sup.c, and R.sup.d are all H. In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, and R.sup.c are H, and R.sup.d comprises an optionally substituted C.sub.1-6 aliphatic group. In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, and R.sup.c are H, and R.sup.d is methyl. In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, and R.sup.c are H, and R.sup.d is CH.sub.2Cl. In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, and R.sup.c are H, and R.sup.d is CH.sub.2OR.sup.y, CH.sub.2OC(O)R.sup.y, where R.sup.y is as defined above. In certain embodiments, methods of the present invention comprise treating heterocycles where R.sup.a, R.sup.b, and R.sup.c are H, and R.sup.d is CH.sub.2CH(R.sup.c)OH, where R.sup.c is as defined above and in the classes and subclasses herein.

[0324] In certain embodiments, methods of the present invention comprise the step of contacting ethylene oxide with carbon monoxide in the presence of any of the catalysts defined hereinabove or described in the classes, subclasses and Tables herein. In certain embodiments, the method comprises treating the ethylene oxide with carbon monoxide in the presence of the catalyst until a substantial portion of the ethylene oxide has been converted to beta propiolactone. In certain embodiments, the method comprises treating the ethylene oxide with carbon monoxide in the presence of the catalyst until a substantial portion of the ethylene oxide has been converted to succinic anhydride.

[0325] In certain embodiments, methods of the present invention comprise the step of contacting propylene oxide with carbon monoxide in the presence of any of the catalysts defined hereinabove or described in the classes, subclasses and Tables herein. In certain embodiments, the method comprises treating the propylene oxide with carbon monoxide in the presence of the catalyst until a substantial portion of the propylene oxide has been converted to beta butyrolactone. In certain embodiments, the method comprises treating the propylene oxide with carbon monoxide in the presence of the catalyst until a substantial portion of the propylene oxide has been converted to methyl succinic anhydride.

[0326] In another embodiment, the present invention encompasses methods of making copolymers of epoxides and CO by contacting an epoxide with CO in the presence of any of the catalysts defined hereinabove or described in the classes, subclasses and Tables herein. In certain embodiments, such processes conform to the scheme:

##STR00310##

[0327] where each of R.sup.a, R.sup.b, R.sup.c, and R.sup.d, are as defined above.

[0328] In certain embodiments, methods of the present invention comprise the step of contacting ethylene oxide with carbon monoxide in the presence of any of the catalysts defined hereinabove or described in the classes, subclasses and Tables herein to provide polypropiolactone polymer.

[0329] In certain embodiments, methods of the present invention comprise the step of contacting propylene oxide with carbon monoxide in the presence of any of the catalysts defined hereinabove or described in the classes, subclasses and Tables herein to provide poly-3-hydroxybutyrate polymer.

[0330] In other embodiments, the present invention includes methods for carbonylation of epoxides, aziridines, thiiranes, oxetanes, lactones, lactams, and analogous compounds using the above-described catalysts. Suitable methods and reaction conditions for the carbonylation of such compounds are disclosed in Yutan et al. (J. Am. Chem. Soc. 2002, 124, 1174-1175), Mahadevan et al. (Angew. Chem. Int. Ed. 2002, 41, 2781-2784), Schmidt et al. (Org. Lett. 2004, 6, 373-376 and J. Am. Chem. Soc. 2005, 127, 11426-11435), Kramer et al. (Org. Lett. 2006, 8, 3709-3712 and Tetrahedron 2008, 64, 6973-6978) and Rowley et al. (J. Am. Chem. Soc. 2007, 129, 4948-4960, in U.S. Pat. Nos. 6,852,865 and 7,569,709, all of which are hereby incorporated herein in their entirety.

[0331] In certain embodiments, methods of the present invention comprise the step of carbonylating ethylene oxide by contacting it with carbon monoxide in the presence of any of the catalysts defined hereinabove or described in the classes, subclasses and Tables herein in a continuous process. In certain embodiments, the continuous process includes a catalyst recovery and recycling step where product of the ethylene oxide carbonylation is separated from a product stream and at least a portion of the catalyst from the product stream is returned to the ethylene oxide carbonylation step. In certain embodiments, the catalyst recovery step entails subjecting the product stream to conditions where little CO is present. In certain embodiments, under such CO depleted conditions, the inventive catalyst has improved stability compared to a comparable catalyst lacking any metal coordination moieties.

EXAMPLES

Example 1

[0332] A typical route to a representative catalyst of the present invention is shown in Scheme E1, below:

##STR00311##

[0333] As shown in Scheme E1, a compound of the invention is made from known salicylaldehyde derivative E1-b. Two equivalents of this aldehyde are reacted with a diamine (in this case 1,2-benzenediamine) to afford Schiff base E1-c. This compound is then reacted with diphenyl phosphine followed by diethyl aluminum chloride and sodium cobalt tetracarbonyl to give the active Al(III)-salen catalyst E1-e. Similar chemistries can be applied to synthesis of the catalysts described hereinabove. One skilled in the art of organic synthesis can adapt this chemistry as needed to provide the specific catalysts described herein, though in some cases routine experimentation to determine acceptable reaction conditions and functional group protection strategies may be required.

Example 2

[0334] Synthesis of [{tetrakis-(4-nitrilobutyl)phenyl-porphyrin} Al(THF).sub.2][Co(CO).sub.4] is shown in Scheme E2, below:

##STR00312##

[0335] As shown in Scheme E2, pyrrole, para (4-butylnitrile)benzaldehyde and salicylic acid are refluxed in xylene to give porphyrin E2-a. E2-a is reacted with diethyl aluminum chloride and then with NaCo(CO).sub.4 in THF to afford the active Al(III)-salen catalyst E2-d. One skilled in the art of organic synthesis can adapt this chemistry as needed to provide the specific catalysts described herein, though in some cases routine experimentation to determine acceptable reaction conditions and functional group protection strategies may be required.

[0336] This application refers to various issued patents, published patent applications, journal articles, and other publications all of which are incorporated herein by reference.

OTHER EMBODIMENTS

[0337] The foregoing has been a description of certain non-limiting embodiments of the invention. Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention.