Fluoride ion mediated reactions of disubstituted acetylenes Me3SiC CMMe3 (M = C, Si, Ge, Sn) with terminal acetylenes

The CsF-18-crown-6 mediated reactions of disubstituted acetylenes Me3SiC eq uivalent to CMMe3 (M = C, Si, Ge, Sn) with phenylacetylene and 2-methyl-5-p yridylacetylene in benzene have been studied. The first step of the reactio n is the deprotonation of aryl acetylene by F- -ion. The carbanion formed i nteracts with the disubstituted acetylene. The silylated, germylated and st annylated acetylenes were formed in yields 26-91%. Quantum chemical calcula tions of trimethylsilyl and trimethylgermyl group transfer have been perfor med. (C) 2001 Elsevier Science B.V. All rights reserved.