维生素E电化学氧化的研究

维生素E又名生育酚,有α、β、γ及δ四种。本文所指的维生素E是α-生育酚即为2,5,7,8-tetramethyl-2-(4',8',12'-trimethyl-tridecyl)-δ-chromanol。其结构式为(图A)及其对映体。它对人体有抗不育症的重要的生物活性,对维生素E的电化氧化机理进行探讨,将有助于揭示它在人体内的氧化化学特性。Kolthoff等人曾研究了维生素E在滴汞电极上的电化学行为。Parker报导了维生素E模型化合物(图B)的阳极氧化,并提出其反应机理。但关于维生素E的阳极氧化机理至今未见报导。本文对维生素E在乙腈、乙醇等不同溶剂中的阳极氧化进行了研究,探讨其氧化

A STUDY OF ELECTROCHEMICAL OXIDATION OF VITAMIN E

In this paper, the mechnism of the electrochemical oxidation of vitamin E in acetonitrile and ethanol solvents was studied by cyclic voltammetry, controlled-potential electrolysis coulometry and double potential step chronoamperometry. The oxidation mechanism of vitamin E was suggested by cyclic voltammogram and compared with V. D. Parker′s work for the model compound of vitamin E. Controlledpotential electrolysis coulometry showed that for the oxidition of each molecule of vitamin E two electrons were transferred. The rate constants of the follow-up hydrolysis and ethanolysis reactions of the primary oxidation product were measured and the relative magnitude of this two kinds of follow-up reactions was compared.