Method and composition for hydrosilylation of carboxylic acid alkenyl esters and hydrogen terminated organosiloxane oligomers with an iridium complex catalyst
A method can selectively prepare a compound of formula (IV), where each R 1 and each R 2 are independently selected from an alkyl group, an aryl group, a halogenated alkyl group, or a halogenated aryl group of 6 to 10 carbon atoms each R 3 is an alkane-diyl group, and each R 4 is hydrogen or an alkyl group. The method involves hydrosilylation of an organohydrogensiloxane oligomer with a carboxylic acid alkenyl ester using an iridium complex catalyst.
1. An acrylate functional organosiloxane polymer of unit formula:
where each R 1 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms;
each R 2 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms;
R 3 is an alkane-diyl group of 1 to 10 carbon atoms;
R 4 is hydrogen or an alkyl group of 1 to 6 carbon atoms;
subscript e is 0 to 10; and
subscript f is greater than 0 to 10.
2. The acrylate functional organosiloxane polymer of claim 1 , where subscript e=0, subscript f=1, and the acrylate functional organosiloxane polymer has formula:
where each R 1 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms; each R 2 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms; R 3 is an alkane-diyl group of 1 to 10 carbon atoms, and R 4 is hydrogen or an alkyl group of 1 to 6 carbon atoms.
3. The acrylate functional organosiloxane polymer of claim 2 , where each R 1 is a methyl group, each R 2 is a methyl group, R 3 is methane-diyl, and R 4 is a methyl group.
4. A method for preparing a product comprising:
1) combining ingredients comprising
(A) an organohydrogensiloxane oligomer of unit formula (VI)
(HR 1 2 SiO 1/2 ) 2 (R 2 2 SiO 2/2 ) e (R 2 HSiO 2/2 ) f ,
where subscript e is 0 to 20, subscript f is 0 to 20, each R 1 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms; each R 2 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms;
(B) a carboxylic acid alkenyl ester of formula (II)
where R 3 is an alkane-diyl group of 1 to 10 carbon atoms, and R 4 is hydrogen or an alkyl group of 1 to 6 carbon atoms; and
(C) an iridium complex of formula (III)
[Ir(R 5 ) b (R 6 ) c ] d ,
where subscript b is 1 or 2, R 5 is a 1,5-cyclooctadiene ligand or a 2,5-norbornadiene ligand, subscript c is 1 or 2, R 6 is a ligand that can be activated off the complex at a temperature less than the boiling point of the organohydrogensiloxane oligomer, and subscript d is 1 or 2;
where the product comprises a compound of unit formula (VII)
with at least 80 mole % selectivity based on all compounds formed by hydrosilylation of ingredients (A) and (B).
5. The method of claim 4 , where each R 1 and each R 2 is a methyl group and subscript e is 0 or 1, and subscript f is 0 or 1.
6. The method of claim 4 , where temperature in step 1) is 50° C. to 70° C.
7. The method of claim 4 , where R 3 is methane-diyl, and R 4 is methyl.
8. The method of claim 4 , where R 5 is 1,5 cyclooctadiene and R 6 is selected from the group consisting of a halogen atom, a beta-ketoester ligand, a halogenated beta-ketoester ligand, an alkoxy ligand, a cyanoalkyl ligand, an aryl ligand, and a heteroaryl ligand.
9. The method of claim 8 , where R 6 is selected from the group consisting of a beta-ketoester ligand, a halogenated beta-ketoester ligand, an alkoxy ligand, a cyanoalkyl ligand, an aryl ligand, and a heteroaryl ligand.
10. The method of claim 4 , where the ingredients in step 1) of the method form a mixture, and the mixture further comprises (D) a solvent, (E) a stabilizer, or two or more of ingredients (D) and (E).
11. The method of claim 4 , where the molar ratio of amounts of ingredient (A) to ingredient (B) [(A):(B) ratio] is 1:1 to 5:1.
12. The method of claim 4 where the amount of ingredient (C) is 1 ppm to 100 ppm.
13. A method for preparing an acrylate functional organosiloxane polymer comprising:
1) combining ingredients comprising
(A) an organohydrogensiloxane oligomer of unit formula (V):
(HR 1 2 SiO 1/2 ) 2 (R 2 2 SiO 2/2 ) e (R 2 HSiO 2/2 ) f ,
where subscript e is 0 to 20, subscript f is 0 to 20, each R 1 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms; each R 2 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms;
(B) a carboxylic acid allyl ester of formula (II)
where R 3 is an alkylene group of 1 to 3 carbon atoms, and R 4 is hydrogen or an alkyl group of 1 to 6 carbon atoms; and
(C) an iridium complex of formula (III)
[Ir(R 5 ) b (R 6 ) c ] d ,
where subscript b is 1 or 2, R 5 is a 1,5-cyclooctadiene ligand or a 2,5-norbornadiene ligand, subscript c is 1 or 2, R 6 is a ligand that can be activated off the complex at a temperature less than the boiling point of the organohydrogensiloxane oligomer, and subscript d is 1 or 2;
where the product comprises a compound of unit formula (VII)
with at least 80 mole % selectivity;
2) combining (a) the compound of formula (VII) with (b) an aliphatically unsaturated organosiloxane polymer and optionally (c) a hydrosilylation catalyst other than the iridium cyclooctadiene complex of formula (III).
14. The method of claim 13 , where the aliphatically unsaturated organosiloxane polymer is a polydiorganosiloxane having aliphatically unsaturated terminal groups.
15. A composition prepared by mixing ingredients comprising:
(A) an organohydrogensiloxane oligomer of unit formula (V):
(HR 1 2 SiO 1/2 ) 2 (R 2 2 SiO 2/2 ) e (R 2 HSiO 2/2 ) f ,
where subscript e is 0 to 20, subscript f is 0 to 20, each R 1 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms; each R 2 is independently an alkyl group of 1 to 6 carbon atoms, an aryl group of 6 to 10 carbon atoms, a halogenated alkyl group of 1 to 6 carbon atoms, or a halogenated aryl group of 6 to 10 carbon atoms;
(B) a carboxylic acid alkenyl ester of formula (II)
where R 3 is an alkylene group of 1 to 6 carbon atoms, and R 4 is hydrogen or an alkyl group of 1 to 6 carbon atoms; and
(C) an iridium complex of formula (III)
[Ir(R 5 ) b (R 6 ) c ] d ,
where subscript b is 1 or 2, R 5 is a 1,5-cyclooctadiene ligand or a 2,5-norbornadiene ligand, subscript c is 1 or 2, R 6 is a ligand that can be activated off the complex at a temperature less than the boiling point of the organohydrogensiloxane oligomer, and subscript d is 1 or 2.