Regiospecific synthesis of 2-allyl-1,2,3-triazoles by palladium-catalyzed 1,3-dipolar cycloaddition

2-Allyl-1,2,3-triazoles were prepared by the palladium-catalyzed three component coupling (TCC) reaction of alkynes, allyl methyl carbonate and trimethylsilyl azide. A pi-allylpalladium azide complex, which undergoes the 1,3-dipolar cycloaddition with alkynes, is proposed as a key intermediate in the TCC reaction. (C) 2002 Published by Elsevier Science Ltd.