Rapid Synthesis of 1,3,5-Substituted 1,2,4-Triazoles from Carboxylic Acids, Amidines, and Hydrazines

A general method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazoles has been developed from reaction of carboxylic acids, primary amidines, and monosubstituted hydrazines. This highly regioselective and one-pot process provides rapid access to highly diverse triazoles.