Boron-Catalyzed Azide Insertion of α-Aryl α-Diazoesters

Abstract

A challenging metal-free azide insertion of α-aryl α-diazoesters in the presence of B(C₆F₅)₃ (5 mol %) was developed for the first time. The reaction features an easy operation, wide substrate scope, and mild conditions and affords the corresponding products in moderate to high yields. More importantly, alkene and alkyne functional groups were well tolerated because no cyclopropanation or cyclopropenation was observed. Furthermore, the corresponding azide products could be converted to primary amines or 1,2,3-triazole derivatives after simple transformations.