Addition of Phenylacetylene to Germasilenes

Abstract

Phenylacetylene has been found to add regioselectively to both tetramesitylgermasilene and Si,Si-di-tert-butyldimesitylgermasilene to give the 3-phenyl-1-sila-2-germacyclobut-3-enes, exclusively. The regioselectivity of the adducts was established by nucleophilic cleavage of the Si−Ge bond using sodium methoxide or hydroxide, respectively, to give the (methoxy- or hydroxysilyl)germylethenes.