One-Pot Synthesis of Coumarins Using 1,1′-Butylenebis (3-sulfo-3H-imidazol-1-ium) Chloride as an Efficient Task-Specific Ionic Liquid

Abstract

Dual solvent-catalytic activity of 1,1′-butylenebis(3-sulfo-3H-imidazol-1-ium) chloride was studied for the synthesis of coumarins under mild conditions. In addition, the catalytic efficiency of some mono- or di-cation ionic liquids containing same counter anion viz. chloride were studied for the model reaction under optimized conditions. The results showed that 1,1′-butylenebis(3-sulfo-3H-imidazol-1-ium) chloride was superior in the yield of the desired product.

Graphical abstract

Keywords:

• Coumarin
• dual solvent-catalyst activity
• eco-friendly conditions
• ionic liquid
• structure-activity relationship

Additional information

Funding

This work was supported by a High Impact Research Grant (NANOCAT RU 2018) for Scientific Research from the University of Malaya, Malaysia. The authors are grateful to staff members in the Analytical and Testing Center of Nanotechnology & Catalysis Research Center, the University of Malaya for partial support of this work.