An unexpected pericyclic reaction between propiolic ester and a 2-vinyl benzofuran

Article abstract of DOI:10.1016/S0040-4020(01)90061-4

A 2:1 adduct of hitherto unknown structure results from heating methyl propiolate 1 and 2-isopropenyl-6-methoxybenzofuran 2. We describe a series of chemical and NMR spectroscopic studies which elucidate the structure of this material, and propose a mechanism for its formation.