Nonaqueous electrochemical oxidation of tamoxifen

作者：Wu Kan; Van Wyck Stephen J; Geiger William E^*

来源：Journal of Electroanalytical Chemistry, 2016, 783: 140-145.

DOI：10.1016/j.jelechem.2016.11.033

• Tamoxifen
• Electrochemical oxidation
• Nonaqueous
• Radical cation
• H-atom abstraction
• Tetrakis(perfluoroaryl)borate anion

The electrochemical oxidation of the chemotherapeutic anti-cancer agent tamoxifen, 1, was studied by voltammetry and electrolysis. Three successive one-electron anodic reactions were observed for 1 in dichloromethane containing weakly-coordinating [B(C6F5)(4)](-) as the supporting electrolyte anion. The first (totally irreversible) oxidation (at 0.64 V vs ferrocene) occurs at the tertiary amine, giving a putative amine radical cation 1(+.) that abstracts a hydrogen atom, most likely from solvent, to give the corresponding ammonium ion 1-H+. The latter is responsible for the two further one-electron oxidations, which take place at the triarylethenyl part of the molecule (E-1/2 values of 0.94 V and 133 V vs ferrocene). Bulk oxidation of 1 at E-appl = 0.6 V produces the ammonium ion 1-H+, which can be cathodically reduced back to neutral tamoxifen in an overall chemically reversible process. The present findings are not consistent with the mechanism described in previous literature for the anodic oxidation of tamoxifen.

• 出版日期2016-12-15