Orthogonal synthesis of pyrroles and 1,2,3-triazoles from vinyl azides and 1,3-dicarbonyl compounds

Tri- and tetrasubstituted N-H pyrroles were prepared by the simple treatment of vinyl azides with 1,3-dicarbonyl compounds in toluene at 100 degrees C via 2H-azirine intermediates generated in situ. When the reactions of vinyl azides and 1,3-dicarbonyl compounds were performed in DMF in the presence of a catalytic amount of K2CO3, 1-vinyl-1,2,3-triazoles were obtained via 1,3-dipolar cycloaddition. These methodologies exploited orthogonal modes of chemical reactivity of vinyl azides, which could be achieved by slight modification of the reaction conditions. (C) 2011 Elsevier Ltd. All rights reserved.