One-Pot Synthesis of Some 2-Amino-4H-chromene Derivatives Using Triethanolamine as a Novel Reusable Organocatalyst under Solvent-Free Conditions and Its Application in Electrosynthesis of Silver Nanoparticles

A wide variety of 2-amino-4H-chromene derivatives with diverse substituents on the 4H-chromene ring were efficiently prepared via one-pot three-component reaction of an aromatic aldehyde and malononitrile with 2-hydroxynaphthalene-1,4-dione, ethyl acetoacetate, or naphthols in the presence of triethanolamine as a new organocatalyst under solvent-free conditions. The procedure is transition metal-free and environmentally friendly approach to various 2-amino-4H-chromene derivatives. Its advantages include short reaction time, high yields, low cost, and straightforward work-up. Triethanolamine is an efficient reusable catalyst. 2-Amino-4H-benzo[g]chromenes (ABgC) were applied as novel components of electro synthesis of silver nanoparticles.