Reductive Coupling of Carbonyl Compounds with Zinc and Trimethylchlorosilane To Produce O-Silylated Pinacols. Effect of Ultrasonic Waves

Article abstract of DOI:10.1021/jo00260a015

Trimethylchlorosilane reacts with carbonyl compounds in the presence of zinc to give O-silylated pinacols, vicinal bis(trimethylsiloxy)alkanes, in good yields via reductive dimerization.This is very mild route to bis(siloxy)alkanes, which are easily converted to pinacols or pinacolones in excellent yields.Electron-donating groups accelerate coupling while electron-withdrawing groups have an inhibiting effect.Cross-coupling reactions yield a mixture of bis(siloxy)alkanes.Ultrasonic irradiations of these reactions increases the yields up to 50percent compared to stirring at the same temperature.