Collect. Czech. Chem. Commun. 1991, 56, 1279-1286

Structural effects in the oxidation of ketones by acid iodate

Prerepa Manikyamba

Department of Chemistry, Arts and Science College, Subedari, Warangal – 506 010 (A.P.) India


The kinetics of oxidation of aliphatic, alicyclic and aryl alkyl ketones by acid iodate has been studied in aqueous methanol medium. The reaction exhibits first order dependence each on [iodate] and [ketone]. The reaction is acid catalysed and a medium of low dielectric constant is favourable for the oxidation process. The oxidation rates are slower than the enolisation rates of the ketones. The mechanism proposed involves rate limiting attack of IO+2 on the enol form of the ketone leading to the formation of an intermediate carbonium ion which undergoes solvolysis, ultimately leading to the formation of a methoxy derivative. The order of reactivity of these structurally different ketones is discussed in terms of stability of the enol formed from the ketone and of the stability of the carbonium ion formed due to attack of the oxidant species in the slow step.