MCM-41 catalyzed rapid and efficient one-pot synthesis of polyhydroquinolines via the Hantzsch reaction under solvent-free conditions

A one-pot four-component reaction of aldehydes, 5,5-dimethyl-1,3-cyclohexanedione, ethyl acetoacetate and ammonium acetate has efficiently been carried out in the presence of 1mol% of MCM-41 as a heterogeneous catalyst in a solvent-free media at 90 degrees C to form the corresponding polyhydroquinoline derivatives via the Hantzsch reaction. The present methodology offers several advantages such as excellent yields, simple procedure, short reaction time (15-25 min), milder conditions and the remarkable reusability of the catalyst, MCM-41. (c) 2007 Elsevier B.V. All rights reserved.