Mechanistic investigation of the oxidation of Cefuroxime by hexacyanoferrate(III) in alkaline conditions

The reactions of Cefuroxime (CFA) by hexacyanoferrate (III) (HCF(III)) in alkaline medium at a constant ionic strength has been studied spectrophotometrically. It is a first order reaction, but fractional order in both CFA and alkali. Decrease in dielectric constant of the medium decreases the rate of reaction. The effect of added products and ionic strength has also been investigated. A mechanism involving free radicals is proposed. In a composite equilibrium step, CFA binds to HCF(III) to form a complex that subsequently decomposes to the products. The main two products were separated and identified by column chromatography, TLC and FT-IR. There is good agreement between the observed and calculated rate constants under different experimental conditions. The reaction was studied at different temperatures and activation parameters were computed with respect to the slow step of the proposed mechanism.