Three-component reaction between imidazoles, isocyanates, and cyanophenylacetylene: a short-cut to N-(Z)-alkenylimidazole-2-carboxamides

1-Substituted imidazoles, isocyanates, and cyanophenylacetylene react under mild (rt), non-catalytic solvent-free conditions to give (Z)-(2-cyano-1-phenylethenyl)imidazole-2-carboxamides in up to 72% yields and with ca. 100% stereoselectivity. The reaction starts from the initial formation of zwitterion/carbene intermediates captured by the isocyanate as the electrophile followed by migration of the alkenyl moiety from the N-3 atom to the anionic center at the carboxamide nitrogen. Thus, the reaction provides an easy access to a novel family of functionalized imidazoles.