Kinetics Of Oxidation Of Organic Compound By Diperiodatonickelate(IV) Ion In Alkaline Medium Spectrophotometrically

The studies of oxidation of some simple organic compounds by tetravalent nickel complex in previous works, the view that the complex existed form is [Ni(OH)2(H3IO6)2]2- was proposed. The complex was dissociated in the process of reaction, then it regarded as the active species and produced adduct with reductant. At last, the reaction was completed through electron-transfer.The kinetics and mechanism of oxidation of alcohols with an ortho group and a series of amino acids by dihydroxydiperiodatonickelate(â…£) in alkaline medium through spectrophotometric method were investigated. Furthermore, the two-electron transfer mechanism of deprotonated complexes [Ni(OH)2(H2IO6)]- as the active species was proposed. Through the studies, the oxidized group itself would affect the reaction rate, namely, the rate of -NH3 is larger than that of -ROH. In addition, the different ortho group of oxidized group also affect the ability to the formation of the adduct between the active species and the organic compound, like the oxidation of some series of amino acids, the larger the spatial hindrance of ortho group is, the slower the reaction rate is, which further affect the various kinetic characterization. The mechanism with the basis of experimental observation could explain well the reaction process, meanwhile, the rate constants and activation parameters were obtained at different temperatures. Based on the above description of reaction systems, the hypothesis that complex was existed as the deprotonated form was supported by experimental results, which greatly denied the existed form of previous works. The present discuss and study will provide certain theoretical foundation for the reaction route design of the organic synthesis and quantitative analysis of analytical chemistry.