Nanocrystalline ZSM-5 based bi-functional catalyst for two step and three step tandem reactions

Abstract

A Pd nanoparticle decorated nanocrystalline ZSM-5 catalyst was prepared for one-pot tandem reactions. The catalyst was characterized by the complementary combination of X-ray diffraction, N₂-adsorption, electron microscopy, and NH₃-temperature programmed desorption techniques. The catalyst was investigated in the one-pot tandem conversion of benzyl alcohol to 1,3-diphenyl-3-(phenylamino)propan-1-one, (E)-chalcone, and 2,3-dihydro-1,5-benzothiazepine. 1,3-Diphenyl-3-(phenylamino)propan-1-one and (E)-chalcone were prepared by two step tandem reactions from benzyl alcohol, whereas 2,3-dihydro-1,5-benzothiazepine was prepared by a three step tandem reaction from benzyl alcohol. A recycling study shows that no significant decrease in the catalytic activity was observed even after three recycles. To the best of our knowledge, this is the first report which deals with such a simple route to prepare 2,3-dihydro-1,5-benzothiazepines in a one-pot tandem methodology from benzyl alcohol.