TiCl4/ nano-γ-Al2O3 promoted one- pot synthesis of 1,4-dihydropyridine derivatives under solvent-free conditions

چکیده مقاله

The classical Hantzsch reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful 1,4-dihydropyridine derivatives.1 Some of biological activity of 1,4-dihydropyridine derivatives are vasodilator, bronchodilator, antiatherosclerotic, antidiabetic, antitumor and antiinflammatory agents.2 TiCl4/ nano-γ-Al2O3 , as an efficient supported Lewis acid catalyst, was synthesized via reaction of nano-γ-Al2O3 with TiCl4 in chloroform at room temperature. The catalyst was characterized with FTIR, FESEM, EDS and XRD methods and applied for Hantzsch reaction. The reaction between an aldehyde,1,3- dicarbonyl and ammonium acetate was examined for preparation of 1,4-dihydropyridines in the presence of TiCl4/ nano-γ-Al2O3 as catalyst under solvent free conditions.