Deshydrocondensation de Thiols β-Germanies a Liaison Ge-H: Synthese de Germathietannes et Digermadithiannes Nouvelle Voie d'Acces aux Germathiones

Abstract

2-(diethylhydrogermyl)ethanethiol, Et₂Ge(H)CH₂CH₂SH, is synthesized by reduction of the corresponding β-thioacetoxybromogermane. This derivative with a Ge-H bond leads by intramolecular dehydrocondensation with a metallic catalyst (Raney Ni, (Ph₃P)₃RhCl) to a new thiagermacyclobutane. The decomposition of this heterocycle by β-elimination and formation of ethylene and transient germathione, EtGe=S, is observed. This intermediate is characterized by ring expansion reaction with the thiagermacyclobutane and formation of digerma-dithiane and by addition on the germanium-sulfur bond of Et₃GeSMe.