| Investigation of mimetic oxygenase not only has important theoretic significance to reveal reversible bonding and activating oxygen as well as the mechanism of oxidation reaction in organism, but also is promising applicable in chemically separating oxygen and realizing high efficiency and selectivity of catalytic oxidation reaction under a mild condition. Many researches have indicated that synergetic action could be operated between the functional groups and the bonded crown ether, especially for the aza crown ether. Unfortunately, up to now very limited studies on the crowned Schiff basees were reported, needless to say, no studies on the oxygenation, catalytic oxidation and mimetic mono-oxygenase performance of aza crowned Schiff base complexes were carried out. In this paper, A series of novel aza crowned mono and bis-Schiff base ligands and its transition-metal complexes were synthesized, the further study on the influence of the introduced crown ring, its size, bonded fashion, position to Schiff base, distance from the coordination center, hetero-atom of crown ring, its complexation with the added alkalic (or alkalic earth) cation as well as the substitutents in the aromatic ring on the dioxygen affinities and biomimetic catalytic oxidation performance were investigated. Series of useful and creative results have been obtained, which give much helpful information to the design and synthesis of new models of mimetic oxygenase.Two series of novel ligands HLsn, H2Ldm (n= 3-17, m= 4, 6) and its transition-metal complexes were synthesized by the reaction sites of secondary amino group of aza crown ether and aromatic ring of benzo crown ether as well asthe convenient modification of SchifF basea, and characterized by IR, 'HNMR, MS and elemental analysis. The crystallographic data of HLs4, HLs15 and CoL2s4 indicates that the special conformational control of nitrogen atom in aza crown ring makes aza crown ring bonded to Schiff base close nearer to the coordination center, and control more efficiently the coordination environment compared with the benzo crown ring.The effect of ligand structure on the oxygenation performance of Co(II) complexes was investigated systematically. Their equilibrium constants Koj and thermodynamic constants ΔH0 and ΔS0 for oxygenation in the presence of diethyleneglycol dimethy ether as solvent and pyridine as axial ligand over a range of -5 0C to 25 0C were determined. The further UV-Vis spectra on the oxygenation demonstrated that the Co(II) complexes possess excellent dioxygen affinities. The results indicated: 1. The oxygenation equilibrium constants Ko2 of all the crowned Schiff base Co(II) complexes was higher than that of the corresponding uncrowned analogues, and the crown ring boned to Schiff base resulted to higher oxygenation velocity and oxygenation capacity, moreover, the bonded fashion and size and number of crown ring all effected the oxygenation. 2. The crown ring and alkalic ion complexed by the crown ring can conduce to the formation and stability of bond of Co-02. 3. aza crown ring close nearer to the coordination center and result to a higher dioxygen affinities compared to the peroxa crown ring.With the aid of Schiff base Mn(III) complexes as cytochrome P-450 article models, catalytic oxidation of olefm with molecular oxygen (O2) as terminal oxidants was carried out under an approximate physiological condition. The influence of crown ring and its size, structure,'bonding fashion, position and the distance from activity center on the oxidation of styrene were examined. It is surprising that the bonded crown ring changed wholly the reaction path of catalytic oxidation of styrene. Crowned Mn (III) Complexes catalyzed the styrene to benzaldehyde-at 100% selectivity and 36 of TOF, but the uncrowned analogues catalyzed oxidation for styrene-to-phenyl-ethylene-epoxide at > 80% of selectivity and 25 of TOF, moreover, the conv. and TOF of catalytic oxidation for styrene tobenzaldehyde has increased by 100% ~ 240% because of the addition of alkalic...
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