Kinetics and mechanism of uncatalyzed and ruthenium(III)-catalyzed oxidation of formamidine derivative by hexacyanoferrate(III) in aqueous alkaline medium

Journal of Chemical Sciences

AHMED FAWZY1 2¹ 

[1] Chemistry Department, Faculty of Applied Sciences, Umm Al-Qura University, 21955 Makkah, Saudi Arabia $$

关键词: Kinetics;    mechanism;    oxidation;    ruthenium(III) catalysis;    formamidine;    hexacyanoferrate(III).;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

The catalytic effect of ruthenium(III) on the oxidation of N,N-dimethyl-N-(4H-1,2,4-triazol-3-yl) formamidine (ATF) by hexacyanoferrate(III) (HCF) was studied spectrophotometrically in aqueous alkalinemedium. Both uncatalyzed and catalyzed reactions showed first order kinetics with respect to [HCF],whereas the reaction orders with respect to [ATF] and $[OH^{-}]$ were apparently less than unity over the concentrationrange studied. A first order dependence with respect to $[Ru^{III}]$ was obtained. Increasing ionic strengthincreased the rate of uncatalyzed reaction and decreased the rate of the catalyzed one Plausible mechanisticschemes of oxidation reactions have been proposed. In both cases, the final oxidation products are identifiedas aminotriazole, dimethyl amine and carbon dioxide. The rate laws associated with the reaction mechanismsare derived. The reaction constants involved in the different steps of the mechanisms were calculated. Theactivation and thermodynamic parameters have been computed and discussed.

【 授权许可】

Unknown