高配位シリカートを活性種とするトリアルコキシシリルエノールエーテルの不斉反応

抄録

Trialkoxysilyl compounds have attracted a lot of attentions because they possess unique reactivities that their related compounds, trimethylsilyl derivatives, do not. We found that lithium dibromobinaphtholate is an effective catalyst activating trialkoxysilyl enol ethers in the aldol reaction with aldehydes. The aldol reaction of 1-trimethoxysilyloxy-3H-indene and cyclohexanecarbaldehyde catalyzed by lithium binaphtholate prepared from (R)-3,3'-dibromo-2,2'-binaphthol and n-BuLi afforded the corresponding syn-adduct predominantly with high enantioselectivity. The present reaction provides the first example of base-catalyzed enantioselective aldol reaction of trialkoxysilyl enol ethers with carbonyl compounds.

Scheme 1