Process for the synthesis of oligomeric siloxane having sulfone moiety, and silicon-containing compounds having sulfone moiety
There is provided herein a process for the synthesis of sulfonyl silanes. There is also provided herein various sulfenylated and sulfonylated silicon-containing compounds made by the process.
1. A process for the synthesis of sulfonyl silanes, comprising the steps of:
(a) reacting a compound of formula (I):
X—(R*) n —S—R (I)
with a metal (M) selected from the group consisting of Li, Na, Mg, Al, Cs, Sn, Ni, and Hg,
to obtain a sulfenyl metal intermediate of the formula (II):
(X) a -M-[(R*) n —S—R] b (II)
(b) contacting the sulfenyl metal intermediate (II) with a silane of formula (III):
Si(X) 2 (R 1 ) 2 (III)
to obtain a sulfenylated silicon-containing reaction product, wherein the sulfenylated silicon-containing reaction product is a sulfenylated silane, and treating the sulfenylated silane with water to form a sulfenylated siloxane;
(c) contacting the sulfenylated siloxane with an oxidizing agent,
and wherein X is a halogen selected from the group consisting of Cl, Br and I; each subscript n is an integer from 1 to 10; each R is H or a monovalent organic group having from 1 to 12 carbon atoms; each R* is a divalent organic group having from 1 to 8 carbon atoms; and, each R 1 is a monovalent organic group having from 1 to 12 carbon atoms; the subscript a is 0 or 1; and, the subscript b is an integer of from 1 to 10, with the proviso that when a is 0, then b is from 1 to 10, and when a is 1, then b is 1.
2. The process of claim 1 , wherein the sulfenylated silicon-containing reaction product of step (b) is of the formula (IVa):
Q-Si(R 1 ) 2 —(R*) n —S—R (IVa)
where Q is Q 1 or Q 2 , wherein Q 1 is a halogen selected from the group consisting of Cl, Br and I;
and Q 2 is a moiety of the formula —(R*) n —S—R.
3. The process of claim 2 , wherein Q is a halogen selected from the group consisting of Cl, Br and I.
4. The process of claim 2 , wherein Q is a moiety of the formula —(R*) n —S—R.
5. The process of claim 2 , wherein R and R 1 are each methyl, each
R* is —(CH 2 )—,
and each n is an integer from 2 to 4.
6. The process of claim 1 , wherein in step (b)
the sulfenyl metal intermediate of formula (II) is contacted with the silane of formula (III) wherein the silane of formula (III) is present in molar stoichiometric excess with respect to the sulfenyl metal intermediate of formula (II).
7. The process of claim 1 , wherein in step (b) the sulfenyl metal intermediate (II) is contacted with the silane of formula (III) by recurrent addition of the sulfenyl metal intermediate of formula (II) to the silane of formula (III).
8. The process of claim 7 , wherein the recurrent addition is performed by dispensing the sulfenyl metal intermediate of formula (II) dropwise to the silane of formula (III).
9. The process of claim 1 , wherein the sulfenylated siloxane is represented by the general formula (V):
R—S—(R*) n —Si(R 1 ) 2 —O—[Si(R 1 ) 2 —O] x —Si(R 1 ) 2 —(R*) n —S—R (V)
wherein each R and R 1 are each independently a monovalent aliphatic group of from 1 to 12 carbon atoms, each R* is a divalent organic group of from 1 to 8 carbon atoms, each subscript n is an integer from 1 to 10 and the subscript x is an integer from 0 to 10.
10. The process of claim 1 , wherein the sulfenylated silicon-containing reaction product of step (b) is treated with a base and the water prior to step (c) to form the sulfenylated siloxane.
11. The process claim 1 , wherein the oxidizing agent of step (c) is selected from the group consisting of oxygen, ozone, hydrogen peroxide, and an organic peroxide.
12. The process of claim 1 , wherein one or more of the process steps (a), (b) or (c) is carried out in the presence of an initiator.
13. The process of claim 12 , wherein the initiator is selected from the group consisting of dihaloalkanes, metal iodides and iodine.