Pericyclynosilanes: synthesis of a new class of cyclic organosilicon compounds

Abstract

The pericyclynosilanes, systematically known as cyclopoly(silapropynylenes), (R₂SiCC)_n(where R = Me or Ph, n 5) have been synthesised, in high yield, by the reaction of the dilithium derivatives of diorganodiethynylsilanes with the corresponding diorganodichlorosilanes, and the dodecamethyl (n= 6) and dodecaphenyl (n= 6) derivatives have been isolated and fully characterised; when the organic substituents present in the diorganodiethynylsilane differ from those of the diorganodichlorosilane, a redistribution reaction is observed, leading to a product in which the organosilicon units are randomly distributed.