Kinetics and Mechanism of Oxidative Decarboxylation of Glycine by Bi(V) in Phosphoric Acid Medium

Abstract

Kinetics of oxidative decarboxylation of glycine by Bi(V)-phosphato complex have been investigated in phosphoric acid-perchloric acid mixture. The products are ammonia, carbon dioxide and formaldelyde. The reaction shows first order kinetics in [oxidant] and [substrate] as well as to [H⁺]. Ionic strength has inverse effect on the reaction rate. The effect of Bi(III) is found to be negligible. Thermodynamic activation parameters have been evaluated. An outer sphere mechanism involving fission of C–C bond and consistent with the observed kinetics has been probed and the rate law derived as: 1                              1                           1 ––––––– = –––––––––––––– + –––– K_obs               K₁K₂k₃[S][H⁺]           k₃