Synthesis of substituted naphtho[1,2-<i>b</i>]benzofuran-7(8<i>H</i>)-ones <i>via</i> photoinduced rearrangement of 4<i>H</i>-chromen-4-one derivatives

Abstract

A simple and efficient method was developed for the synthesis of substituted naphtho[1,2-b]benzofuran-7(8H)-ones based on the photorearrangement reaction of 4H-chromen-4-one derivatives. The studied reaction includes the photocyclization of the hexatriene system, [1,9]-H-sigmatropic rearrangement and heterocyclic ring opening. The starting terarylenes were prepared via a new three-component tandem condensation of 3-(dimethylamino)-1-(2-hydroxyaryl)prop-2-en-1-ones, arylglyoxals and cyclic 1,3-diketones.