TMSCl-mediated synthesis of α,β-unsaturated amides via C-C bond cleavage and C-N bond formation of propargyl alcohols with trimethylsilyl azide.

Abstract

A new method with high efficiency for the synthesis of α,β-unsaturated amides from the easily prepared propargyl alcohols and TMSN3 using TMSCl as an acid promoter is developed. A wide variety of α,β-unsaturated amides were produced in moderate to excellent yields. Mechanistic studies indicate that this transformation involves TMSCl-mediated allenylazide intermediate formation, C-C bond cleavage, and C-N bond formation. Significantly, this reaction shows good functional group compatibility and high regioselectivity, with a relatively short reaction time and inexpensive reagents.