Electrochemical Reaction Mechanism of Tiron in Acidic Aqueous Solution

Abstract:

Electrochemical oxidation of tiron in the presence of H2O as a nucleophile in strongly acidic aqueous solutions was studied by cyclic voltammetry, controlled-voltage coulometry and spectrometric investigations. The mechanism of electrochemical reaction is confirmed by spectrophotometric tracing in various times of controlled-voltage coulometry. The voltammetric and spectrophotometric foundations indicate that a 1,4-Michael addition of H2O from its hydroxy moiety to the position 4 of electrochemically derived o-quinone is occurred. The electrochemical oxidation and reduction of tiron has been successfully accomplished by controlled-voltage coulometry in a redox flow-through type cell and the final electro-reduced product was characterized by spectrophotometric, 1H NMR and mass spectrometric methods. It is demonstrated that the electro-oxidation of tiron follows an ECE mechanism in acidic aqueous solutions, leading to formation of a new compound of para- benzoquinone derivative.

• Periodical: Advanced Materials Research (Volumes 396-398)
• Pages: 1730-1735
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.396-398.1730
• Online since: November 2011
• Authors: Yan Xu, Yue Hua Wen, Jie Cheng, Gao Ping Cao, Yu Sheng Yang
• Keywords: Controlled-Voltage Coulometry, Cyclic Voltammetry (CV), Electro-Oxidation, Michael Addition, Spectrometric Analysis, Tiron

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