Réactivité des trialcoylalcoxy‐ et dialcoylalcoxychlorogermanes et de leurs isologues soufrés vis à vis des aldéhydes et des cétones

Abstract

AbstractAldehydes and ketones add onto the germanium‐oxygen bond of triethylmethoxy‐ and diethylmethoxy‐chlorogermanes with formation of the corresponding germanium acetals, the stability, the mode of thermal decomposition and certain properties of which have been investigated.The germanium acetals of hexafluoroacetone are stable. β‐Elimination reactions are observed from germanium acetals of chloral and hexachloroacetone. The decomposition of the germanium acetals of the aldehydes and ketones takes place, in the presence of H2PtCl6, to give the corresponding acetals of the starting carbonyl compounds and trialkylgermanium oxides.Additions and decompositions of the same type are observed in the action of the aliphatic aldehydes on the trialkyl(alkylthio)‐ and dialkyl(alkylthio)‐chlorogermanes. Chloral gives a reversible insertion reaction, however, at 90°, besides the β‐elimination reaction, a chlorine‐methylthio exchange reaction is also observed with formation of tri(methylthio)acetaldehyde and triethyl‐germanium chloride.The influence of the inductive effects of the substituents on the germanium or on the carbonyl group in the course of these reactions as well as the catalytic action of the chloroplatinic acid or of zinc chloride seem to confirm the addition mechanism considered.