Propane-1,2,3-triyl tris(hydrogen sulfate): A mild and efficient recyclable catalyst for the synthesis of biscoumarin derivatives in water and solvent-free conditions

A simple, efficient, and ecofriendly procedure has been developed using propane-1,2,3-triyl tris(hydrogen sulfate) as a catalyst for the synthesis of biscoumarin derivatives in water and solvent-free conditions. The significant features of the present protocol are simplicity, environmentally benign, high yields, no chromatographic separation, and recyclability of the catalyst.

Graphical abstractBiscoumarin derivatives were readily prepared in short times with good yields through the reaction of an aldehyde and 4-hydroxycoumarin in water or solvent-free conditions in the presence of propane-1,2,3-triyl tris(hydrogen sulfate).Figure optionsDownload full-size imageDownload as PowerPoint slide