Reusable homogeneous cobalt pyridine diimine catalysts for dehydrogenative silylation and tandem dehydrogenative-silylation-hydrogenation
View Patent ↗Disclosed herein are cobalt complexes containing terdentate pyridine di-imine ligands and their use as efficient, reusable, and selective dehydrogenative silylation, crosslinking, and tandem dehydrogenative silylation-hydrogenation catalysts.
1. A process for producing a silylated product comprising:
(i) reacting a mixture comprising (a) an unsaturated compound containing at least one unsaturated functional group, (b) a silyl hydride containing at least one silylhydride functional group, and (c) a catalyst, optionally in the presence of a solvent, in order to produce a dehydrogenatively silylated product, wherein the catalyst is a complex of the Formula (I) or an adduct thereof;
wherein
each occurrence of R 1 , R 2 , R 3 , R 4 , and R 5 is independently hydrogen, C1-C18 alkyl, a C1-C18 substituted alkyl, an aryl, a substituted aryl, or an inert substituent, wherein one or more of R 1 -R 5 , other than hydrogen, optionally contain at least one heteroatom; each occurrence of R 6 and R 7 is independently C1-C18 alkyl, C1-C18 substituted alkyl, aryl or substituted aryl, wherein R 6 and R 7 optionally contain at least one heteroatom; optionally any two of R 1 -R 7 vicinal to one another, R 1 -R 2 , and/or R 4 -R 5 taken together may form a ring being a substituted or unsubstituted, saturated or unsaturated cyclic structure, with the proviso that R 1 -R 7 and R 8 -R 6 are not taken to form a terpyridine ring; and
L is hydroxyl, or a C1-C18 alkyl, C1-C18 substituted alkyl, aryl, or substituted aryl group, wherein L optionally contains at least one heteroatom; and
(ii) using the catalyst complex to conduct subsequent reactions to produce additional dehydrogenatively silylated product and/or a saturated silylated product.
2. The process of claim 1 further comprising removing the complex and/or derivatives thereof from the dehydrogenative silylated product in operation (i).
3. The process of claim 2 , wherein using the catalyst complex in operation (ii) comprises reacting, in a separate system, the complex and/or derivatives thereof removed from the dehydrogenative silylated product in operation (i) with an unsaturated compound containing at least one unsaturated functional group and a silyl hydride containing at least one silylhydride functional group.
4. The process of claim 1 , wherein operation (ii) comprises adding additional unsaturated compound (a) and silyl hydride (b) to the system, and repeating reacting operation (i) in the presence of said catalyst (c) to produce additional dehydrogenatively silylated product.
5. The process of claim 1 , wherein operation (ii) comprises reacting said dehydrogenatively silylated product in-situ with hydrogen in the presence of said catalyst (c) to produce a saturated and silylated product.
6. The process of claim 4 further comprising reacting said dehydrogenatively silylated product and/or said additional dehydrogenatively silylated product in-situ with hydrogen in the presence of said catalyst (c) to produce a saturated and silylated product.
7. The process of claim 1 wherein the dehydrogenatively silylated product comprises a silane or siloxane containing a silyl group and an unsaturated group.
8. The process of claim 3 , wherein the unsaturated group is in the alpha or beta position relative to the silyl group.
9. The process of claim 1 , wherein the molar ratio of the unsaturated group in said component (a) relative to the silylhydride functional group in said component (b) is less than equal to 1:1.
10. The process of claim 9 , wherein the silane or siloxane of the dehydrogenatively silylated product contains one silyl group derived from component (b).
11. The process of claim 9 , wherein the dehydrogenatively silylated product contains two or more terminal silyl groups derived from component (b).
12. The process of claim 9 , wherein said process produces an α,ω-substituted alkane or alkene diol from a parent α,ω-bis(silyl) substituted alkane or alkene.
13. The process of claim 1 , wherein the molar ratio of the unsaturated group in said component (a) relative to the silylhydride functional group in said component (b) is greater than 1:1.
14. The process of claim 13 , wherein the silane or siloxane contains two or more silyl groups derived from component (b).
15. The process of claim 1 , wherein said component (a) is a mono-unsaturated compound.
16. The process of claim 1 , wherein said component (a) is selected from the group consisting of an olefin, a cycloalkene, an alkyl-capped allyl polyether, a vinyl-functional alkyl-capped allyl or methallyl polyether, an alkyl-capped terminally unsaturated amine, an alkyne, terminally unsaturated acrylate or methacrylate, unsaturated aryl ether, vinyl-functionalized polymer or oligomer, vinyl-functionalized silane, vinyl-functionalized silicone, unsaturated fatty acids, unsaturated esters, and combinations thereof.
17. The process of claim 12 , wherein said component (a) is selected from the group consisting of N,N-dimethylallyl amine, allyloxy-substituted polyethers, cyclohexene, linear alpha olefins, internal olefins, branched olefins, unsaturated polyolefins, a vinyl siloxane of the Formula (VII), and combinations thereof, wherein Formula (VII) is
wherein each occurrence of R 20 is independently a C1-C18 alkyl, C1-C18 substituted alkyl, C3-C18 terminal alkenyl, vinyl, aryl, or a substituted aryl, and n is greater than or equal to zero.
18. The process of claim 1 , wherein said component (b) is selected from the group consisting of R a SiR 4-a , (RO) a SiR 4-a , HSiR a (OR) 3-a , R 3 Si(CH 2 ) f (SiR 2 O) k SiR 2 H, (RO) 3 Si(CH 2 ) f (SiR 2 O) k SiR 2 H, Q u T v T p H D w D H x M H y M z , and combinations thereof, wherein Q is SiO 4/2 , T is R′SiO 3/2 , T H is HSiO 3/2 , D is R′ 2 SiO 2/2 , D H is R′HSiO 2/2 , M H is HR′ 2 SiO 1/2 , M is R′ 3 SiO 1/2 , each occurrence of R and R′ is independently C1-C18 alkyl, C1-C18 substituted alkyl, aryl, or substituted aryl, wherein R and R′ optionally contain at least one heteroatom, each occurrence of a independently has a value from 1 to 3, f has a value of 1 to 8, k has a value of 1 to 11, p is from 0 to 20, u is from 0 to 20, v is from 0 to 20, w is from 0 to 1000, x is from 0 to 1000, y is from 0 to 20, and z is from 0 to 20, provided that p+x+y equals 1 to 3000, and the valences of the all the elements in the silyl hydride are satisfied.
19. The process of claim 14 , wherein p, u, v, y, and z are from 0 to 10, w and x are from 0 to 100, wherein p+x+y equals 1 to 100.
20. The process of claim 1 , wherein said component (b) has one of the following structures:
wherein each occurrence of R 21 , R 22 , R 23 , R 24 , and R 25 is independently a C1-C18 alkyl, C1-C18 substituted alkyl, aryl, or substituted aryl, R 26 is hydrogen, a C1-C18 alkyl, C1-C18 substituted alkyl, aryl, or substituted aryl, x and w are independently greater than or equal to 0 (x is at least equal to 1 for Formula IX)), and a and b are integers from 0 to 3 provided that a+b=3.
21. The process of claim 1 , wherein at least one of R 6 and R 7 is
wherein each occurrence of R 9 , R 10 , R 11 , R 12 , and R 13 is independently hydrogen, C1-C18 alkyl, C1-C18 substituted alkyl, aryl, substituted aryl, or an inert substituent, wherein R 9 -R 13 , other than hydrogen, optionally contain at least one heteroatom.
22. The process of claim 21 , wherein R 9 and R 13 are independently methyl, ethyl or isopropyl groups and R 11 is hydrogen or methyl.
23. The process of claim 22 , wherein R 9 , R 11 , and R 13 are each methyl.
24. The process of claim 1 , wherein R 1 and R 5 are independently methyl or phenyl groups.
25. The process of claim 1 , wherein R 2 , R 3 and R 4 are hydrogen.
26. The process of claim 1 , wherein the complex is immobilized on a support.
27. The process of claim 26 , wherein the support is selected from the group consisting of carbon, silica, alumina, MgCl 2 , zirconia, polyethylene, polypropylene, polystyrene, poly(aminostyrene), sulfonated polystyrene, dendrimers, and combinations thereof.
28. The process of claim 26 , wherein at least one of R 1 to R 7 contains a functional group that covalently bonds with the support.
29. The process of claim 1 , wherein the catalyst is generated in-situ by contacting a catalyst precursor with an activator in the presence of a liquid medium containing at least one component selected from the group consisting of a solvent, the silyl hydride, the compound containing at least one unsaturated group, and combinations thereof, wherein the catalyst precursor is represented by structural Formula (III)
wherein
each occurrence of R 1 , R 2 , R 3 , R 4 , and R 5 is independently hydrogen, C1-C18 alkyl, a C1-C18 substituted alkyl, an aryl, a substituted aryl, or an inert substituent, wherein one or more of R 1 -R 5 , other than hydrogen, optionally contain at least one heteroatom; each occurrence of R 6 and R 7 is independently C1-C18 alkyl, C1-C18 substituted alkyl, aryl or substituted aryl, wherein R 6 and R 7 optionally contain at least one heteroatom; optionally any two of R 1 -R 7 vicinal to one another, R 1 -R 2 , and/or R 4 -R 5 taken together may form a ring being a substituted or unsubstituted, saturated or unsaturated cyclic structure, with the proviso that R 1 -R 7 and R 8 -R 6 are not taken to form a terpyridine ring; and
X is an anion selected from the group consisting of F − , Cl − , Br − , I − , CF 3 R 14 SO 3 − or R 15 COO − , wherein R 14 is a covalent bond or a C1-C6 alkylene group, and R 15 is a substituted or unsubstituted C1-C10 hydrocarbyl group;
and wherein the activator is a reducing agent or an alkylating agent selected from the group consisting of NaHBEt 3 , CH 3 Li, DIBAL-H, LiHMDS, and combinations thereof.
30. The process of claim 1 , wherein the reaction is conducted under an inert atmosphere.
31. The process of claim 1 , wherein the reaction is conducted in the presence of a solvent selected from the group consisting of hydrocarbons, halogenated hydrocarbons, ethers, and combinations thereof.
32. The process of claim 1 , wherein the reaction is carried out at a temperature of −40° C. to 200° C.
33. A composition produced from a process according to claim 1 , wherein the composition contains the catalyst and/or derivatives thereof.
34. The composition of claim 33 , comprising at least one component selected from the group consisting of silanes, silicone fluids, crosslinked silicones, or a combination of two or more thereof.
35. A process for producing a crosslinked material, comprising reacting a mixture comprising (a) a silyl-hydride containing polymer, (b) a mono-unsaturated olefin or an unsaturated polyolefin, or combinations thereof and (c) a catalyst, optionally in the presence of a solvent, in order to produce the crosslinked material, wherein the catalyst is a complex of the Formula (I) or an adduct thereof
wherein
each occurrence of R 1 , R 2 , R 3 , R 4 , and R 5 is independently hydrogen, C1-C18 alkyl, a C1-C18 substituted alkyl, an aryl, a substituted aryl, or an inert substituent, wherein one or more of R 1 -R 5 , other than hydrogen, optionally contain at least one heteroatom; each occurrence of R 6 and R 7 is independently C1-C18 alkyl, C1-C18 substituted alkyl, aryl or substituted aryl, wherein R 6 and R 7 optionally contain at least one heteroatom; optionally any two of R 1 -R 7 vicinal to one another, R 1 -R 2 , and/or R 4 -R 5 taken together may form a ring being a substituted or unsubstituted, saturated or unsaturated cyclic structure, with the proviso that R 1 -R 7 and R 8 -R 6 are not taken to form a terpyridine ring; and
L is hydroxyl, or a C1-C18 alkyl, C1-C18 substituted alkyl, aryl, or substituted aryl group, wherein L optionally contains at least one heteroatom.
36. The process of claim 35 , wherein the reaction is conducted under an inert atmosphere.
37. The process of claim 35 , wherein the reaction is conducted in the presence of a solvent selected from the group consisting of hydrocarbons, halogenated hydrocarbons, ethers, and combinations thereof.
38. The process of claim 35 , wherein the reaction is carried out at a temperature of −40° C. to 200° C.
39. The process of claim 1 , wherein the catalyst is present in an amount of from about 0.1 mol % to about 5 mol %.
40. The process of claim 5 , wherein the catalyst is present in an amount of from about 0.1 mol % to about 5 mol %.