Spectroscopic Investigation and Reactivities of Ruthenium(III) Catalyzed Oxidation of Anticholinergic Drug Atropine Sulfate Monohydrate by Hexacyanoferrate(III) in Aqueous Alkaline Media: A Mechanistic Approach

Abstract

The kinetics of oxidation of an atropine sulfate monohydrate (ASM) by hexacyanoferrate (HCF) (III) has been investigated spectrophotometrically in presence of ruthenium(III) catalyst in aqueous alkaline medium at 25°C. The stoichiometry is 1: 2. The reaction is first order in HCF(III) and has less than unit order in ASM concentrations. The effect of ionic strength and dielectric constants were studied on the rate of reaction. The active species of oxidant and catalyst are Fe(CN)₆ ^3– and [Ru(H₂O)₅(OH)]²⁺, respectively. A suitable mechanism is proposed. The catalytic constant (K_C) was also calculated. The activation parameters and thermodynamic quantities are also determined and discussed.

Keywords:

• atropine sulfate
• hexacyanoferrate(III)
• kinetics
• mechanism
• oxidation

Acknowledgments

The authors thank the UGC, New Delhi for providing the financial assistance to carryout this work (Project No: F.NO.39-833/2010).