Diisobutylaluminum Hydride Promoted Cyclization of 1-Hydrosilyl-4-silyl-1,3-enynes to Polysubstituted Siloles

Org Lett. 2017 Feb 17;19(4):882-885. doi: 10.1021/acs.orglett.7b00038. Epub 2017 Feb 1.

Abstract

An efficient method for preparing unsymmetrically multisubstituted siloles is described. The reaction of 1-hydrosilyl-4-silyl-1,3-enynes with diisobutylaluminum hydride (DIBAL-H) gave multisubstituted siloles in good to high yields. This method could be applied to the synthesis of benzosiloles using 2-hydrosilyl-1-(silylethynyl)benzenes as substrates. The silole formation was also promoted even by a substoichiometric amount of DIBAL-H. The reaction provides a straightforward method to prepare siloles and benzosiloles.