New Methods and Reagents in Organic Synthesis. 18. Homologation of Ketones with Trimethylsilyldiazomethane (TMSCHN₂)

Abstract

Trimethylsilyldiazomethane (TMSCHN₂) easily reacts with various ketones in the presence of boron trifluoride etherate in methylene chloride solution to give chain- or ring-homologated ketones, and can be used as a stable and safe substitute for hazardous diazomethane. The reaction proceeds below 0°C during 1-4h, and permits much more efficient homologation than can be achieved with diazomethane.