Synthesis of N-unsubstituted 1,2,3-triazoles via aerobic oxidative N-dealkylation using copper(II) acetate
[ 1 ] Sogang Univ, Dept Chem, 35 Baekbeomro Mapogu, Seoul 04107, South Korea
A copper-catalyzed aerobic oxidative C-N bond cleavage reaction was developed for the synthesis of 4-substituted-NH-1,2,3-triazoles. Diverse beta-ketotriazoles derivatives, which are the starting materials for the aerobic oxidative C-N bond cleavage reaction, were prepared from nine aryl and seven alkyl alkynes and alpha-azidoacetophenone by a copper(l)-catalyzed [3 + 2]cycloaddition reaction. The aerobic oxidation of alpha-(1,2,3-triazol-1-yl)acetophenones using a catalytic amount of copper(II) acetate in the presence oxygen under neutral conditions gave the title compounds in high yield. (C) 2017 Elsevier Ltd. All rights reserved.