The oxygenation constants (InKO2) and thermodynamic parameter (ΔHo, ΔSo) of Novel Co (II) complexes with dihydroxamic acids functionalized N-pivot lariat ether CoL1~CoL4 and the uncrowned analogue CoL5 were measured. Their catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) was investigated. The enhancement of O2-binding and catalytic oxidation activities by the oxa aza crown ether ring of the cobalt complexes as well as the complexed alkali metal and alkaline-earth metal ions were discussed.

Liang-Jun LONG, Xing-Yue WEI, Xing-Min WANG and Ning LI