KINETICS AND MECHANISM OF OXIDATION OF TETRAHYDROFURFURYL ALCOHOL BY DIHYDROXYDIPERIODATONICKELATE-(IV) COMPLEX IN AQUEOUS ALKALINE-MEDIUM

The kinetics of oxidation of tetrahydrofurfuryl alcohol by dihydroxydiperiodatonickelate (IV) complex in the temperature range of 20-35-degrees-C has been studied by spectrophotometry in aqueous alkaline medium. The reaction order in [Ni(IV)] was found to be unity and that in [alcohol] to be 1.64-1.69. The rate of oxidation increases with increase in [OH-] and decreases with increase in [IO4-], indicating that dihydroxymonoperiodatonickelate (IV) complex is the reactive species of oxidant. Salt effect studies indicated that the reaction is of ion-dipole type. Under the protection of nitrogen the reaction system does not induce polymerization of acrylonitrile or acrylamide, which indicates that a one-step two-electron transfer mechanism without free radical intermediate may be in operation. A mechanism involving a preequilibrium of an adduct formation between Ni(IV) and alcohol has been proposed. All the experimental phenomena can be explained by the equation derived from the mechanism. The activation parameters of the rate-determining step have been calculated.