Abstract: An efficient Cu/OMS-2-catalyzed oxidative heterogeneous protocol has been developed for the synthesis of tetrasubstituted unsymmetrical 1,4-enediones and 4H-pyrido[1,2-a]-pyrimidin-4-ones from 1,4-enediones and amines or 2-aminopyridines. The present catalytic system employs air as the terminal oxidant and tolerates a broad range of substrates using low loading copper (1.3 wt%). The Cu/OMS-2 was characterized by various methods, including XRD, XPS, BET as well as TEM/SEM, and the results of H-2-TPR shows that the redox ability of the catalyst was improved by the combination of Cu and OMS-2. Moreover, the catalyst is recyclable. KeyWords Plus: OCTAHEDRAL MOLECULAR-SIEVES; TEMPERATURE CO OXIDATION; AREA CUO-CEO2 CATALYSTS; TERMINAL ARYL ALKENES; WET AIR OXIDATION; METHYL KETONES; UNSYMMETRICAL 1,4-ENEDIONES; ISOMALABARICANE TRITERPENES; 1,3-DICARBONYL COMPOUNDS; BIOMIMETIC APPROACH Published in RSC ADVANCES, 5 (106):87221-87227; 10.1039/c5ra17351e 2015
|