Synthesis of fluorine containing <i>N</i>‐benzyl‐1,2,3‐triazoles and <i>N</i>‐methyl‐pyrazoles from conjugated alkynes

Abstract

Abstract magnified image 1, 3‐Dipolar‐cycloaddition reaction of fluoro substituted 3‐aryl‐propynenitriles 1 with benzyl azide 2 afforded the expected 3‐benzyl‐5‐aryl‐3 H ‐[1,2,3]triazole‐4‐carbonitrile 3 and 1‐benzyl‐5‐aryl‐1 H ‐[1,2,3]‐triazole‐4‐carbonitrile 4 in good yield. However, 1,3‐dipolar cycloaddition of diazomethane 5 with 3‐aryl‐propynenitriles 1 resulted in the exclusive formation of N ‐methyl‐pyrazole derivatives 6 and 7 .