1,3-Dipolar cycloaddition reactions of enaminones and azides: Synthesis of 4-acyl-1,2,3-triazoles and mechanistic studies

4-acyl-1,2,3-triazoles are an important and versatile chemical scaffold widely applied in medicinal chemists due to their interesting pharmacological properties. Acknowledging the constant need for a greener, simple and scalable methodology in medicinal chemistry, herein we report the synthesis of new 4-acyl-1,2,3-triazoles through the metal-free and solvent-free cycloaddition reactions between enaminones and aryl azides, obtaining yields of 41–77%. Based on experimental Hammett correlation and theoretical Quantum calculations data a reaction mechanism for 3-dipolar cycloadditions synthesis of 4-acyl-1,2,3-triazoles was proposed.