Chitosan-ZnO Nanocomposite Nanocatalyst for the Synthesis of 12-Azatetraphene-8-one and 7-Azatetraphene-11-one Derivatives via Unsymmetrical Hantzsch-Like Reactions

The chitosan-ZnO nanocomposite nanocatalyst was employed as a robust, recyclable, and environmentally benign catalyst to efficiently facilitate the regioselective Hantzsch-like multicomponent reactions involving one-mole equivalent of an aldehyde, 1(2)-naphthyl amine, and dimedone. The reactions afforded tetrahydrobenzo-[<i>c</i>]-acridin-8-one and tetrahydrobenzo-[<i>a</i>]-acridin-11-one derivatives. The formed structures were assigned based on 2D-NMR. The same products have been obtained from the reaction of cyclic enaminones with aldehydes in acetic acid.