Negishi Approach to 1,5-Disubstituted 3-Amino-1H-1,2,4-triazoles.

An efficient synthesis of 1,5-disubstituted 3-amino-1H-1,2,4-triazoles has been achieved via a Negishi coupling of aryl or vinyl bromides and 1-substituted 3-amino-1H-1,2,4-triazoles in the presence of Knochel's base tetramethylpiperidinylzinc chloride lithium chloride (TMPZnCl·LiCl) and catalytic bis(di-tert-butylphenylphosphine)palladium chloride. This chemistry tolerates a variety of electronically diverse aryl or vinyl bromides and 1-substituted 3-amino-1H-1,2,4-triazoles.