Diversity Oriented Synthesis of Oxygen-Heterocycles, Warfarin Analogs Utilizing Microwave-Assisted Dimethyl Urea-Based Deep Eutectic Solvents

Abstract

Deep eutectic solvent (DES) catalyzed, Microwave-assisted one-pot conjugate Michael addition followed by annulation of nucleophiles, 4-hydroxy coumarin, 1,3-diketone with α,β-unsaturated carbonyl compounds (chalcones) toward benzopyran, pyranocoumarin, xanthene, dihydrofuran, 4-hydroxy-coumarin (warfarin analogs) derivatives has been achieved. It is a one-pot, solvent, metal-free, and green chemical approach with a clean reaction pathway, in high regio, stereo selectivities, and yields under milder MW-irradiation. The easily recoverable DES catalyst and eco-friendly reaction strategy are notable advantages of the current procedure.

Keywords:

• Benzopyrans
• deep eutectic solvents
• pyranocoumarins
• warfarin analogs
• xanthenes

Acknowledgments

The authors are thankful to SIF-VIT for providing NMR, GC-MS, FT-IR and other instrumentation facilities.

Disclosure statement

The authors declare no competing financial interest.