Studies On The Functional Coordination Compounds And Metallomicelle Used As The Mimics Of Hydrolase And Peroxidase

The study of natural enzyme aroused the concern of both chemists and biologists because of its high selectivity, catalytic activity and mild reactive condition in chemical reaction. Various simple or complicated chemical systems have been used as mimic models for natural enzyme. Through investigating mimic enzyme, the mechanism of the enzymatic catalytic reaction and the correlation between the structure, character and function of the enzyme were explored, which should lay a theoretic foundation for designing and synthesizing the catalyst of simple structure, high selectivity, high catalytic activity and mild reactive condition in the chemical reaction; and should be favorable to develop green catalyst with practical value.The catalytic action of various kinds of functional coordination compound and metallomicelles which are made from the complex and micelle, used as mimic hydrolase or peroxidase, have been studied respectively in catalyzing the phosphatic diester hydrolysis and the phenolic derivant oxidation, in the paper. Some new results have been obtained.The studies on BNPP hydrolysis catalyzed by Schiff base transitional metal complexes of various structures (used as the mimic model of the phosphatic diester hydrolase catalyzed BN PP hydrolysis) in aqueous solution and micellar solution discovered the following: 1) the catalytic activity of two Schiff base transitionalmetal complexes containing the side chain are higher than that of the simple Schiff base transitional metal complexes. The BNPP hydrolysis catalyzed by the Schiff base transitional metal complexes with or without a side chain all obey the mechanism of the metal - hydroxide ion, the synergism between the hydroxide or alkyl oxygen group on the side chain of the Schiff base and hydroxide ion coordinated to metal ion in the complex accelerates the rate of the substrate hydrolysis; 2) the activity of the crown Schiff base transitional metal complexes is higher than that of the simple Schiff base complex in aqueous or micellar solution. The higher the hydrophobicity of the crown group is, the higher the catalytic activity of the relevant complex is. In BNPP hydrolysis catalyzed by the Schiff complexes, the crown group not only affords a proper microenvironment which is favorable to the formation of the intermediate between complex and BNPP, but also assists metal ion to transfer a coordinated water molecule to OH-, which is favorable to achieve the nucleophilic substituent reaction inside molecule.The catalytic activity of the oxamido-bridged dinuclear copper(II) complex and the metallomicelle made from the complex and the surfactant, used as the mimic models of the dinuclear metal hydrolase in catalyzing BNPP hydrolysis, has been investigated. The results of the studies indicate that the mimic models have high catalytic activity. These catalytic reactions follow the bifunctional mechanism of Lewis acid activation and metal hydroxide activation. There is synergism between two metal ions inside the complex, its performance is regulated by the distance of two metal ions.Different micelles and metallomicelles made from the Schiff base transitional metal complex and different surfactants have different activities in catalyzing BNPP hydrolysis, the order of the catalytic activities is Brij35> LSS >CTAB.The catalysis of some mimetic models of natural peroxidase in the phenol and phenolic derivant oxidation was investigated. Some new results are obtained from the studies: 1) a novel thermokinetic research method, the characteristic reduced parameter method, has been proposed, and the kinetics of oxidation of benzoquinoneby hydrogen peroxide has also been investigated with this method; 2) the kinetic mathematical models that the metallomicelles made from the mono-nuclear or dinuclear complexes and surfactants catalyze the phenolic derivant oxidation have been established respectively; 3) the feasibility and mechanism that the metallomicelle, a mimetic model of peroxidase, catalyzes the phenolic derivant oxidation has been discussed.The new results obtained...