KINETIC AND MECHANISTIC STUDIES IN THE OXIDATIVE REGENERATION OF CARBONYL COMPOUNDS FROM OXIMES BY BIS[DIPYRIDINESILVER(I)] DICHROMATELokesh Mathur, Vasudha Ranga, Garima Goswami, Saraswati Agarwal, Pradeep K. Sharma.
The oxidative deoximination of several aldo- and keto-oximes by bis[dipyridinesilver(I)] dichromate (BDSD), in dimethylsulphoxide
(DMSO), exhibited a first order dependence on BDSD. A Michaelis-Menten type kinetics was observed with respect to oximes. The
oxidation of ketoximes is slower than that of aldoximes. The rates of oxidation of aldoximes correlated well in terms of Pavelich-Taft dual
substituent-parameter equation. The low positive value of polar reaction constant indicated 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 is suggested.
Key words: carbonyl compounds; bis[dipyridinesilver(I)] dichromate, kinetics; mechanism; oxidation; oximes.