Trifluoroacetic Anhydride-Catalyzed Oxidation of Isonitriles by DMSO: A Rapid Convenient Synthesis of Isocyanates

摘要

A smooth and efficient oxidation of isonitriles to isocyanates by sulfoxides is catalyzed by trifluoroacetic anhydride. Using DMSO as the oxidant and 5 mol-% TFAA (dichloromethane, −60 °C to 0 °C), the process is complete in a few minutes, forming dimethylsulfide as the only byproduct. The newly-formed isocyanates may be used directly or isolated in high purity by solvent evaporation.