β-Cyclodextrin-assisted synthesis of Biginelli adducts under solvent-free conditions

A simple, green and efficient protocol was developed using β-cyclodextrin as a solid catalyst for the solvent-free synthesis of various Biginelli adducts. The advantages of our protocol included the following: (i) a metal-free methodology; (ii) high yields; (iii) simple and efficient work-up procedures; (iv) improved results under solvent-free conditions. β-cyclodextrin-catalyzed the Biginelli reactions for various aldehydes, demonstrating that it is an efficient and eco-friendly catalyst for the preparation of heterocyclic compounds.