Catalysts and methods for polymer synthesis

• US 8,956,989 B2
• Filed: 01/31/2013
• Issued: 02/17/2015
• Est. Priority Date: 08/22/2008
• Status: Active Grant

• Current Assignee: Saudi Aramco Technologies Company
• Original Assignee: Novomer, Inc (Danimer Scientific, Inc.)
• Inventors: Allen, Scott D., Cherian, Anna E., Simoneau, Chris A., Farmer, Jay J., Coates, Geoffrey W., Gridnev, Alexei, LaPointe, Robert E.
• Primary Examiner(s): Truong, Duc
• Application Number:
  US13/755,126
• Publication Number:
  US 20130144033A1
• Time in Patent Office: 747 Days
• Field of Search: 528/405, 528/412, 528/480, 502/102, 502/104
• US Class Current: 502/102
• CPC Class Codes: B01J 2531/0238 Complexes comprising multidentate ligands, i.e. more than 2 ionic or coordinative bonds from the central metal to the ligand, the latter having at least two donor atoms, e.g. N, O, S, P
• CPC Class Codes: B01J 2531/025 Ligands with a porphyrin ring system or analogues thereof, e.g. phthalocyanines, corroles
• CPC Class Codes: B01J 2531/0252 Salen ligands or analogues, e.g. derived from ethylenediamine and salicylaldehyde
• CPC Class Codes: B01J 2531/0294 "Non-innocent" or "non-spectator" ligands, i.e. ligands described as, or evidently, taking part in the catalytic reaction beyond merely stabilizing the central metal as spectator or ancilliary ligands, e.g. by electron transfer to or from the central metal or by intra-/intermolecular chemical reactions, e.g. disulfide coupling, H-abstraction
• CPC Class Codes: B01J 2531/31 Aluminium
• CPC Class Codes: B01J 2531/62 Chromium
• CPC Class Codes: B01J 2531/845 Cobalt
• CPC Class Codes: B01J 31/0239 Quaternary ammonium compounds
• CPC Class Codes: B01J 31/0259 comprising phosphorous acid (-ester) groups ((RO)P(OR')2) or the isomeric phosphonic acid (-ester) groups (R(R'O)2P=O), i.e. R= C, R'= C, H
• CPC Class Codes: B01J 31/0265 Phosphazenes, oligomers thereof or the corresponding phosphazenium salts polyphosphazenes per se C07F9/067
• CPC Class Codes: B01J 31/182 comprising aliphatic or saturated rings
• CPC Class Codes: B01J 31/183 with more than one complexing nitrogen atom, e.g. phenanthroline
• CPC Class Codes: B01J 31/1835 comprising aliphatic or saturated rings
• CPC Class Codes: B01J 31/2243 At least one oxygen and one nitrogen atom present as complexing atoms in an at least bidentate or bridging ligand
• CPC Class Codes: C07C 251/24 having carbon atoms of imino groups bound to carbon atoms of six-membered aromatic rings
• CPC Class Codes: C07C 2601/14 The ring being saturated
• CPC Class Codes: C07C 279/12 being further substituted by nitrogen atoms not being part of nitro or nitroso groups
• CPC Class Codes: C07D 213/53 Nitrogen atoms
• CPC Class Codes: C07D 487/04 Ortho-condensed systems
• CPC Class Codes: C07D 487/22 in which the condensed system contains four or more hetero rings
• CPC Class Codes: C07F 15/065 : without a metal-carbon linkage
• CPC Class Codes: C07F 19/005 : without metal-C linkages
• CPC Class Codes: C07F 9/5355 : Phosphoranes containing the structure P=N-
• CPC Class Codes: C07F 9/6561 : containing systems of two or more relevant hetero rings condensed among themselves or condensed with a common carbocyclic ring or ring system, with or without other non-condensed hetero rings
• CPC Class Codes: C08F 4/80 : selected from iron group metals or platinum group metals
• CPC Class Codes: C08G 64/34 : and cyclic ethers

Abstract

The present invention provides unimolecular metal complexes having increased activity in the copolymerization of carbon dioxide and epoxides. Also provided are methods of using such metal complexes in the synthesis of polymers. According to one aspect, the present invention provides metal complexes comprising an activating species with co-catalytic activity tethered to a multidentate ligand that is coordinated to the active metal center of the complex.

Claims

1. A metal complex for the synthesis of aliphatic polycarbonate polymers comprising a cobalt salen complex, wherein the salen ligand has an activating moiety tethered to the position ortho to a metal-bound oxygen substituent of one or both of the salicylaldehyde-derived phenyl rings of the salen ligand,

wherein each activating moiety has a formula (Z)_m, and comprises a linker “

”

coupled to at least one activating functional group Z , with m denoting the number of activating functional groups present on a single linker moiety;

m is an integer from 1 to 4;

the linker comprises an optionally substituted C_2-30 aliphatic group wherein one or more methylene units are optionally and independently replaced by —

NR^y—

, —

N(R^y)C(O)—

, —

C(O)N(R^y)—

, —

O—

, —

C(O)—

, —

OC(O)—

, —

C(O)O—

, —

S—

, —

SO—

, —

SO₂—

, —

C(═

S)—

, —

C(═

NR^y)—

, or —

N═

N—

;

where each occurrence of Ry is independently —

H, or an optionally substituted radical selected from the group consisting of C_1-6 aliphatic, 3- to 7-membered heterocyclic, phenyl, and 8- to 10- membered aryl; and

Z comprises a neutral nitrogen-containing functional group, a cationic functional group, or an arsonium functional group.

2. The metal complex of claim 1, wherein the cobalt salen complex comprises a substructure independently selected from the group consisting of:

3. The metal complex of claim 1, wherein Z comprises a neutral nitrogen-containing functional group.

4. The metal complex of claim 1, wherein the neutral nitrogen-containing functional group comprises a guanidine or amidine.

5. The metal complex of claim 3, wherein the neutral nitrogen-containing functional group is selected from the group consisting of:

6. The metal complex of claim 1, wherein the linker “

”

comprises an optionally substituted C_3—

C₃₀ aliphatic group.

7. The metal complex of claim 1, wherein the linker “

”

comprises an optionally substituted C_4—

C₆ aliphatic group.

8. The metal complex of claim 1, wherein the linker “

”

comprises an optionally substituted C₄ aliphatic group.

9. The metal complex of claim 1, wherein the linker “

”

comprises an optionally substituted C₃ aliphatic group.

10. The metal complex of claim 1, wherein the linker “

”

comprises an optionally substituted straight alkyl chain.

11. The metal complex of claim 1, wherein the linker “

”

is selected from the group consisting of;

12. The metal complex of claim 1, wherein the cobalt has an oxidation state of 3+.

13. The metal complex of claim 1, wherein there are activating moieties tethered to the positions ortho and para to the phenolic oxygen of one or both of the salicylaldehyde-derived phenyl rings of a salen ligand.

14. The metal complex of claim 1, wherein m is 1.

15. The metal complex of claim 1, wherein m is greater than 1.

16. The metal complex of claim 1, wherein Z is a cationic functional group selected from the group consisting of:

17. The metal complex of claim 16, wherein the cationic moiety comprises a guanidinium group.

18. The metal complex of claim 16, wherein the cationic moiety comprises an amidinium group.

19. The metal complex of claim 16, wherein the linker “

”

comprises an optionally substituted C_3-C₃₀ aliphatic group.

20. The metal complex of claim 16, wherein the linker “

”

comprises an optionally substituted C_4-C₆ aliphatic group.

21. The metal complex of claim 16, wherein the linker “

”

comprises an optionally substituted C₄ aliphatic group.

22. The metal complex of claim 16, wherein the linker “

”

comprises an optionally substituted C₃ aliphatic group.

23. The metal complex of claim 16, wherein the linker “

”

comprises an optionally substituted straight alkyl chain.

24. The metal complex of claim 16, wherein the linker “

”

is selected from the group consisting of;

25. The metal complex of claim 16, wherein the cobalt has an oxidation state of 3+.

26. The metal complex of claim 16, wherein there are activating moieties tethered to the positions ortho and para to the phenolic oxygen of one or both of the salicylaldehyde-derived phenyl rings of a salen ligand.

27. The metal complex of claim 16, wherein m is 1.

28. The metal complex of claim 16, wherein m is greater than 1.

29. The metal complex of claim 1, wherein Z is an arsonium group.

30. The metal complex of claim 29, wherein the arsonium group comprises:

31. The metal complex of claim 30, wherein the arsonium group is selected from the group consisting of:

32. A polymerization method comprising the step of contacting an epoxide with carbon dioxide in the presence of an effective amount of a metal complex of claim 3.

33. The polymerization method of claim 32, wherein the neutral nitrogen-containing functional group is selected from the group consisting of:

34. The polymerization method of claim 32, wherein the epoxide is selected from the group consisting of:

ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, 1,2 octene oxide, 3-vinyl cyclohexene oxide, epichlorohydrin and mixtures of any two or more of these.

35. The polymerization method of claim 32, wherein the epoxide is ethylene oxide, propylene oxide, or cyclohexene oxide.

36. The polymerization method of claim 32, wherein the epoxide is ethylene oxide.

37. The polymerization method of claim 32, wherein the epoxide is propylene oxide.

38. A polymerization method comprising the step of contacting an epoxide with carbon dioxide in the presence of an effective amount of a metal complex of claim 16.

39. The polymerization method of claim 38, wherein the epoxide is selected from the group consisting of:

ethylene oxide, propylene oxide, butylene oxide, cyclohexene oxide, 1,2 octene oxide, 3-vinyl cyclohexene oxide, epichlorohydrin and mixtures of any two or more of these.

40. The polymerization method of claim 38, wherein the epoxide comprises ethylene oxide, propylene oxide, or cyclohexene oxide.

41. The polymerization method of claim 38, wherein the epoxide comprises ethylene oxide.

42. The polymerization method of claim 38, wherein the epoxide comprises propylene oxide.