Catalytic Properties of Monomeric and Oligomeric Cu(II) Phenylhydrazono Imine Chelates Immobilized on Zeolite with a Topological Anchor

摘要

Heterogeneous catalysts for liquid-phase oxidation of cyclohexene with molecular oxygen were prepared by topological-anchor immobilization on CaA zeolite of a monomeric Cu(II) chelate with N,N'-tri-methylenebis(2-methyl-1-benzoylglyoxal 1-phenylhydrazone 2-imine) and of an oligomeric product of its condensation with ethylenediamine.The samples prepared contain surface monomeric and oligomeric Cu(II) chelates oriented toward the reaction medium,which makes them accessible to reactant molecules.The catalytic properties of the above monomeric chelate are preserved in going to the oligomers.The apparent rate constants per metal center for both homogeneous (soluble monomeric chelate) and heterogeneous modes coincide,suggesting the pseudohomogeneous behavior of the supported samples.The topological-anchor immobilization of insoluble oligomeric Cu(II) polychelates on zeolite leads to their more efficient utilization as heterogeneous catalysts and can be considered as one of examples of combining advantages of homogeneous and heterogeneous catalysis.