Electrochemical logic to synthesize disilanes and oligosilanes from chlorosilanes

Abstract

Oligosilanes are important compounds in industrial and synthetic chemistry. Here, we develop a general approach for the synthesis of linear and cyclic oligosilanes via the reductive activation of readily available chlorosilanes. The efficient and selective generation of silyl anion intermediates, which are arduous to achieve by other means, allows for the synthesis of various novel oligosilanes. In particular, this work presents a modular synthesis for a variety of functionalized cyclosilanes, which may give rise to materials with distinct properties from linear silanes but remain challenging synthetic targets. In comparison to the traditional Wurtz coupling, our method features milder conditions and improved chemoselectivity, broadening the functional groups that are compatible in oligosilane preparation. Computational studies support a mechanism whereby differential activation of two sterically and electronically distinct chlorosilanes are achieved in an electrochemically driven radical-polar crossover mechanism.