Study On The Oxidation Of Cumene And Ethylbenzene Catalyzed By Biomimetic Oxygenase Systems

N-substituted hydroxamic acid and salicyl schiff base cobalt(II) complexes have been designed in an attempt to mimic oxygenases to activate oxygen and catalyze the oxidation of organic substrates under wild reaction conditions(ambient pressure and relatively lower temperature).The oxidation of cumene and ethylbenzene catalyzed by the catalyst systems have been studied. Some useful and new results have been obtained.Four N-substituted hydroxamic acid and four salicyl schiff base cobalt(II) complexes have been synthesized. The structures of the new two ligands and the new complexes were characterized by IR,UV, MS,1H NMR, XRD, conductivity measurement, elemental analysis. The oxygenation of the models and the catalytic properties of them in the oxidation of cumene and ethylbenzene in homogenous system have been studied. The effect of reaction conditions on the oxidation has also been studied. The results demonstrate that the catalytic properties of the models have relation to their oxygenation i.e. the higher the oxygenation equilibrium constants are, the higher the catalytic properties are.The green catalysts system soluble biomimetic oxygenases /phase transfer catalyst which possesses the advantages of homogenous and heterogeneous catalyst has been designed. Compared with the biomimetic oxygenases hi homogenous system, the new system is characterized by wilder reaction conditions, faster reaction speed, higher catalytic property and selectivity, and the easy process of the separation of catalysts and the feasibility of their reuse, which takes on the potential application in industry. The oxidation of cumene and ethylbenzene catalyzed by the catalyst system with air as oxidant at ambient pressure and relatively lower temperature in biphase system has been studied. The results show that w(CHP) is 26%(w/w) and the selectivity of EBHP is 95.1%, which meets the demand hi commercial application respectively.