Role of acidity of pillared inter-layered clay(PILC) for the synthesis of pyridine bases

Abstract

Pillared clay has emerged in recent years as a very good shape-selective solid acid catalyst for various organic chemical transformations. In the present study an attempt has been made to prepare various pillared inter-layered clays (PILC) with inorganic polyoxocations prepared from Al, Zr and mixed Al and Zr salts. Pyridine bases, the important commodity chemicals, are generally prepared by solid acid catalysed reaction between aldehyde and ammonia. In the present study, solid acid-like PILC has been used for the first time as a catalyst for the synthesis of these important chemicals through the cyclodehydrogenation reaction between aldehyde and ammonia. The concentration and strength of the acid sites of clay have been determined by NH3 TPD. An attempt has been made to correlate the acidity with the activity of these catalysts. © 1998 SCI