Cu/C Catalyst for Click Chemistry

Significance

A copper-in-charcoal catalyst for click chemistry was demonstrated. Thus, the Cu/C was prepared from activated wood charcoal and Cu(NO₃)₂ with ultrasonic agitation. Highly efficient click chemistry of benzyl azide and 2-methyl-but-3-yn-2-ol by using Cu/C catalyst (10 mol%) was performed at 60 °C in dioxane to give a 1,4-triazole derivative in 99% yield. The click cycloaddition was significantly accelerated with stoichiometric Et₃N or by microwave irradiation. This Cu/C catalyst was reused without loss of activity under air (1st-3rd use: 99% yield).