A SYNTHESIS OF CARBONYL-SUBSTITUTED 4-ARYL-4H-BENZO[h]CHROMENES BASED ON A THREE-COMPONENT CONDENSATION OF α-NAPHTHOL, AROMATIC ALDEHYDES, AND β-ENAMINONES

Abstract

A three-component condensation of α-naphthol, aromatic aldehydes, and β-enaminones in acetic acid under reflux led to β-carbonylsubstituted (with respect to the pyran oxygen atom) 4-aryl-4H-benzo[h]chromenes. The reaction is a cascade process involving the generation of 1,2-naphthoquinone-2-methide, the Diels–Alder reaction involving push-pull β-enaminone, and the subsequent elimination of a secondary amine.

Authors: Irina А. Semenova, Vitaly А. Osyanin*, Dmitry V. Osipov*, Yuri N. Klimochkin