Oxidative regeneration of carbonyl compounds from oximes by morpholinium chlorochromate: A kinetic and mechanistic study

Abstract

The oxidative deoximination of several aldo- and keto-oximes by morpholinium chlorochromate in dimethyl sulphoxide, exhibits a first order dependence on both the oxime and MCC. The oxidation of ketoximes is slower than that of aldoximes. The rate of oxidation of aldoximes correlate well in terms of Pavelich- Taft dual substituent-parameter equation. The low positive value of polar reaction constant indicates a nucleophilic attack by a chromate oxygen on the carbon. The reaction is subject to steric hindrance by the alkyl groups. The reaction of acetaldoxime has been studied in nineteen different organic solvents. The solvent effect has been analysed by multiparametric equations. A mechanism involving the formation of a cyclic intermediate in the rate-determining step has been proposed.