申请人:Wilson Michael E.
公开号:US08865926B2
公开(公告)日:2014-10-21
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.
本发明实施例涉及在溶剂存在的反应相中,通过与路易斯酸催化剂的存在,使二羟基硅烷或二羟基硅氧烷与二氢硅烷或二氢基硅氧烷缩合,制备离散的环状硅氧烷或环状硅氧烷混合物。控制二羟基硅烷或二羟基硅氧烷和二氢基硅烷或二氢基硅氧烷的引入,使得环缩合发生在稀释SiH和SiOH官能团的反应相中,从而可以高产率地分离出单环缩合加合物,且几乎没有更高分子量的缩合产物。在本发明的一种实施例中,制备了1,1-二苯基-3,3,5,5-四甲基环三硅氧烷,收率非常高。