FeCl3 · 6H2O-Catalyzed Acceleration of the Acylation of Sodium Azide with N-Acylbenzotriazoles

[image omitted] Catalyzed by ferric chloride hexahydrate (FeCl3 · 6H2O), the acylation of sodium azide with N-acylbenzotriazoles was greatly accelerated in a mixed solvent of acetone and water. Thus, good to excellent yields of a variety of acyl azides were obtained at room temperature in a short time. Furthermore, because of the complete conversion of N-acylbenzotriazoles and the easy removal of the by-product, purification by column chromatography was no longer required, which made the protocol suitable for large-scale preparation.