Electrochemical oxygenation of diorganyldichlorosilanes: a novel route to generation of diorganylsilanones

Interaction of diorganyldichlorosilanes R2SiCl2 (R=Me, Et, Ph) with superoxide or peroxide anions, produced in situ by electroreduction of molecular oxygen, provides short-living diorganylsilanones R2SiO. The latter undergo cyclization to give lower perorganylcyclosiloxanes (R2SiO)n, n=3 or 4 and then insert to the molecules of these primary products to form higher cyclic oligomers. When the process is carried out in the presence of a reagent-trap for silanones (hexamethyldisiloxane, hexamethylcyclotrisiloxane), the products of insertion of diorganylsilanones into the molecule-traps (Me3Si(OSiR2)nOSiMe3 with n≥1, and (Me2SiO)3(R2SiO)m with m≥1, respectively) were obtained.