Environmentally Benign Synthesis of 4-Thiazolidinone Derivatives Using a Co/Al Hydrotalcite as Heterogeneous Catalyst

Abstract

The present effort describes facile and environmentally benign synthesis of 4-thiazolidinone via oxidative cyclocondensation of benzyl alcohols, various substituted aromatic anilines and thioglycolic acid using a Co-Al hydrotalcite based heterogeneous catalyst (Co@HT) in methanol act as a solvent. We have synthesized three types of Co@HT with different molar ratio Co@HT-2 (1:1), Co@HT-3 (2:1), Co@HT-4 (3:1). Characterization of synthesized Co@HT catalyst using various analysis techniques such as FT-IR, powder XRD, SEM, XPS, EDS, DTG-TGA and N2 physical adsorption. Among the synthesized hydrotalcite, Co-HT-3 exhibit admirable catalytic activity towards oxidation of benzyl alcohol followed by cyclocondensation of respective aldehydes, anilines and thioglycolic acid into the corresponding 4-thiazolidinones in methanol at 60 οC using O2 as a oxidant. Furthermore, after end of the reaction, the catalyst is easily recovered and eco-friendly without any considerable loss in its catalytic efficiency.