N -Acyl-1,2,3-triazoles - key intermediates in denitrogenative transformations.

Elusive N -acyl-1,2,3-triazoles formed by direct acylation of NH-1,2,3-triazoles were isolated and fully characterized, including X-ray crystallography. A preference for the formation of thermodynamic N 2 isomers was established. Direct evidence of interconversion between N 1- and N 2-acyltriazoles confirmed their value in denitrogenative transformations. Efficient synthesis of enamido triflates from NH-triazoles via the intermediacy of N 2-acyl-1,2,3-triazoles was developed.