Thiamine hydrochloride (Vit-B1): An optimized green alternative for the synthesis of polyhydroquinoline derivatives

Thiamine hydrochloride (Vitamin-B1) has been utilized as an effective biodegradable catalyst for the one pot synthesis of polyhydroquinoline derivatives via four component reaction of dimedone, aldehyde, ethylacetoacetate and ammonium acetate in ethanol under mild conditions. The method presented here offers several advantages over reported procedures in terms of environmentally benign catalytic system and excellent product yields (75-98%) of polyhydroqninoline compounds. Aromatic and heteroaryl aldehyde with electron donating as well as electron withdrawing group undergo smooth reaction to afford the corresponding polyhydroquinoline derivatives. The synthesized polyhydroquinoline compounds were characterized by IR, NMR and Mass spectral data. The present article describes the new application of Vitamin-B1.