Soluble linear polysilanes by Wurtz-type coupling

Abstract

We have conducted a detailed study of the Wurtz coupling synthesis of a number of polysilanes under a variety of reaction conditions. This study has led to a number of interesting observations. In general, for polymerizations using molten sodium, the addition of diglyme results in higher polymer yields. Dialkyldichlorosilanes do not polymerize either at 65°C or in the presence of ultrasound unless an additive such as diglyme or a crown either is included. In the polymerization of dihexyldichlorosilane at lower temperatures, both 15-crown-5 and 12-crown-4 gave similar results and are somewhat more effective than either diglyme or 18-crown-6. Although no single set of reaction conditions is optimal for all monomer classes, the information presented should be helpful in the selection of appropriate conditions based on monomer structure.