Sequential Pd(0)/Fe(III) Catalyzed Azide–Isocyanide Coupling/Cyclization Reaction: One-Pot Synthesis of Aminotetrazoles

Abstract

A rapid and efficient synthesis of aminotetrazole from aryl azides, isocyanides, and TMSN₃ is developed. The reaction is promoted by sequential Pd(0)/Fe(III) catalysis. The reaction sequence utilizes the Pd-catalyzed azide-isocyanide denitrogenative coupling reaction to generate unsymmetric carbodiimide in situ, which reacts with TMSN₃ in the presence of FeCl₃ in a single pot. The methodology has distinct advantages over traditional synthetic approaches where toxic Hg and Pb salts are employed at stoichiometric scale.