Process for the production of cyclosiloxanes
US8865926B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 26, 2011 |
| Grant date | Oct 21, 2014 |
| Priority date | — |
| Expiry date | Jun 15, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F7/21
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Embodiments of the invention are directed to the preparation of a discrete cyclosiloxane or a discrete mixture of cyclosiloxanes where a dihydroxysilane or dihydroxysiloxane condenses with a dihydrosilane or dihydroxysiloxane in the presence of a Lewis acid catalyst in a reaction phase including a solvent. The introduction of the dihydroxysilane or dihydroxysiloxane and dihydrosilane or dihydroxysiloxane is controlled such that the cyclocondensation occurs in a reaction phase that is dilute in the SiH and SiOH functionality permitting the isolation of the monocyclocondensation adduct in high yield with little higher molecular weight condensation products. In one embodiment of the invention 1,1-diphenyl-3,3,5,5-tetramethylcyclotrisiloxane is prepared in very high yield.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.