KINETICS AND MECHANISM OF OXIDATION OF SOME KETONES BY N-BROMOACETAMIDE

Article abstract of DOI:10.1016/S0040-4020(01)90562-9

The kinetics of oxidation of n-butyl methyl ketone (n-BMK) and i-butyl methyl ketone (i-BMK) by N-bromoacetamide (NBA) is studied in perchloric acid media in the presence of mercuric acetate.The main product of the oxidation is the corresponding 1,2-dicarbonyl compound.The reaction order with respect to NBA is zero while with respect to ketone and H+ it is unity.Mercuric acetate, acetamide and sodium perchlorate have negligible effect on the reaction rate, while the dielectric effect is negative.A solvent isotope effect (k₀(D2O)/k₀(H2O) = 1.80-2.05 and 1.70-2.06 for n-BMK and i-BMK, respectively ) at 35 deg C is observed.On the basis of the available evidence a suitable mechanism consistent with the experimental results is proposed in which it is suggested that the mechanistic route for NBA oxidation is through the enol form of the ketone in an acidic medium.