Preparation of sulfur-containing organosilicon compounds using a buffered phase transfer catalysis process

US6534668B2 · kind B2 · utility

Assignee

• Dow Corning Corporation · US

Inventors

• Michael Backer · Mainz, DE
• Howard M. Bank · Freeland, US
• John Gohndrone · Midland, US
• William Charles Maki · Midland, US
• Charles E. Skinner · Midland, US
• Anil Kumar Tomar · Midland, US
• Hongjun Yue · Midland, US

Key dates

• Filing date: Jun 29, 2001
• Grant date: Mar 18, 2003
• Expiry date: Jun 29, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07F7/1892
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the production of sulfur containing organosilicon compounds of the formula:(RO)3−mRmSi—Alk—Sn—Alk—SiRm(OR)3−mwhereR is independently a monovalent hydrocarbon of 1 to 12 carbon atoms; Alk is a divalent hydrocarbon of 1 to 18 carbon atoms;m is an integer of 0 to 2, n is a number from 1 to 8;based on phase transfer catalysis techniques is disclosed. The process comprises reacting:(A) a sulfide compound having the formula M2Sn or MHS,where H is hydrogen, M is ammonium or an alkali metal,n is as defined above, with(B) a silane compound of the formula;(RO)3−mRmSi—Alk—Xwhere X is Cl, Br or I, and m is the same as above, and optionally,(C) sulfurin the presence of a phase transfer catalyst and an aqueous phase containing a buffer.The improvement of the present invention is characterized by adding a buffer to the aqueous phase, which minimizes or prevents gelling of the sulfur containing organosilicon compounds. The present invention also teaches a process for the production of sulfur containing organosilicon compounds by controlling the pH of the aqueous phase.