Introduction of Bulky Substituents at the Bridgehead Position of a 9-Silatriptycene: Pentacoordinate Hydridoorganylsilicates as Intermediates

Abstract

The reaction of 10-phenyl-10-germa-9-silatriptycene (1b) with phenyllithium in THF/HMPA produced 9,10-diphenyl-10-germa-9-silatriptycene (1a), which had hitherto not been accessible. The reaction proceeds by attack of the phenyl anion on 1b via the intermediate silicate anion 7, which was identified by 29Si NMR spectroscopy. The structure of 1a was confirmed by X-ray crystallography. As a model reaction, the attack of phenyllithium on triphenylsilane (8) and diphenylsilane (14) was investigated by 29Si NMR spectroscopy, revealing the formation of a number of novel hydridosilicates analogous to 7.