High pressure and thermal Diels-Alder reaction of 2-vinyl-benzo[b]furan and 2-vinyl-benzo[b] thiophene.: Synthesis of new condensed heterocycles

A new preparation of 2-vinyl-benzo[b]furan and 2-vinyl-benzo[b]thiophene is described. Diels-Alder reactions of these dienes with 3-nitro-2-cyclohexen-1-one and 2-inden-1-one was examined under thermal and high pressure conditions. The reaction products have been converted to multi-ring heteroaromatic compounds. (C) 2001 Elsevier Science Ltd. All rights reserved.