Oxidative kinetics of serine and threonine by N-bromonicotinamide

Postgraduate and Research Department of Chemistry, National College, Trichy-620 001, Tamilnadu, India

E-mail : lathaa_ramesh@yahoo.com            Fax : 91-431-2482995

Manuscript received 26 May 2008, revised 13 June 2008, accepted 10 July 2008

The kinetics of oxidative decarboxylation and deamination of a-amino acids, namely, serine and threonine by N-bromonicotinamide (NBN) in aqueous acetic acid medium (1 : 1) in presence of hydrochloric acid was studied over the temperature range 308-328 K. The oxidation reaction leads to the formation of corresponding aldehydes, CO₂ and NH₃. The reaction does not induce the polymerization of acrylonitrile. The reaction was found to be first order with respect to substrate concentration. Inverse first order was observed with respect to concentration of oxidant and mineral acid. Added nicotinamide retarded the reaction. Mercuric acetate had no significant effect on the reaction rate. A decrease in the dielectric constant of the medium increases the rate. HOBr has been postulated as the reactive oxidizing species in the reaction. The activation parameters were evaluated.