Potassium phthalimide: An efficient and green organocatalyst for the synthesis of 4-aryl-7-(arylmethylene)-3,4,6,7-tetrahydro-1H-cyclopenta[d]pyrimidin-2(5H)-ones/thiones under solvent-free conditions

An efficient synthesis of Biginelli-type compounds using potassium phthalimide as a green, mild, and commercially available organocatalyst in a one-pot, multi-component cyclocondensation reaction of cyclopentanone, aldehydes, and urea/thiourea is reported. The present methodology is a green approach to access 4-aryl-7-(arylmethylene)-3,4,6,7-tetrahydro-1H-cyclopenta[d]pyrimidin-2(5H)-ones/thiones. It offers several merits such as simple operational procedures, no use of hazardous organic solvents, and cheap and environmentally friendly solid basic catalyst.

Graphical abstractA simple, green, and one-pot approach for the synthesis of Biginelli-like scaffolds is described. Potassium phthalimide under neat conditions catalyzed this cyclocondensation process to afford the 1H-cyclopenta[d]pyrimidin-2(5H)-ones/thiones.Figure optionsDownload full-size imageDownload as PowerPoint slide