Green Chemistry: New Synthesis of Substituted Chromenes and Benzochromenes via Three-Component Reaction Utilizing Rochelle Salt as Novel Green Catalyst

Abstract

Substituted 2-amino-4-aryl-7-hydroxy-4H-chromene-3-carbonitriles (6), 2-amino-4-aryl-4H-benzo[h]chromene-3-carbonitriles (7), and 3-amino-1-aryl-1H-benzo[f]chromenes-2-carbonitriles (8) were prepared, in good yields, via one-pot three-component reactions of aromatic aldehydes (1), malononitrile (2), and resorcinol (3) or α-naphthol (4) or β-naphthol (5) in refluxing ethanol or water in the presence of Rochelle salt as novel green heterogeneous and reusable catalyst.