Synthesis of stanna- and germa-cycloheptatrienes

Article abstract of DOI:10.1016/0022-328X(92)80172-T

The first preparations of C-unsubstituted stannacycloheptatriene and germacycloheptatriene, analogues of cycloheptatriene, are described with their spectroscopic properties.A stannacyclohexadienyl anion derived from stannacyclohexadiene by treatment with lithium di-isopropylamide was allowed to react with chlorocarbene generated from dichloromethane and n-butyllithium, and this led to the formation of the corresponding stannacycloheptatriene.The disproportionation reaction between the stannacyclohexadiene and dichlorodimethylgermane gave the corresponding germacyclohexadiene in reasonable yield.In a similar manner, the reaction of the germacyclohexadienyl anion with chlorocarbene yielded C-unsubstituted germacycloheptatriene.