lridium(lll) Chloride Catalysed Oxidation of Propan-2-one by Hexacyanoferrate(III) in Aqueous Alkaline Medium

Chemical Laboratories, University of Allahabad, Allahabad-211 002

Manuscript received 15 January 1983, revised 7 March 1984, accepted 8 June 1985

The kinetic data show direct proportionality with respect to ferrkyanide concentra­tions. The reaction rate is directly proportional to the substrate, OH^- ions and iridium(III) at lower concentrations, but at higher concentrations the rate becomes independent of the substrate, alkali and the catalyst concentrations. These data suggest the formation of an activated complex between the substrate and iridium(III). Toffs complex with ferricyanide gives another complex C₂, which slowly decomposes into the univalent iridium(I) species and the intermediate products which in turn are farther oxidised by ferricyanide ions into the subsequent steps.