Cellulose sulfuric acid catalyzed multicomponent reaction for efficient synthesis of 1,4-dihydropyridines via unsymmetrical Hantzsch reaction in aqueous media

C-5-unsubstituted 1,4-dihydropyridines were obtained in good to excellent yields by proceeding through a simple, mild and efficient procedure utilizing cellulose sulfuric acid (CSA) as a catalyst. The reaction work-up is very simple and catalyst can be easily separated from reaction mixture and reused several times in subsequent reactions. (C) 2010 Elsevier B.V. All rights reserved.