通过电化学控制的化学可逆转化,将α-托科菲罗尔 (维生素E) 转化为其离子
Leodrina L Williams1, Richard D Webster
1Research School of Chemistry, Australian National University, Canberra ACT 0200, Australia.
Journal of the American Chemical Society
|September 30, 2004
概括
阿尔法-托科菲罗尔 (alpha-TOH) 经历可逆电化学氧化,形成稳定的离子. 其氧化产物,包括离子基和二离子,使用先进的电化学和光谱方法进行了表征.
科学领域:
- 电化学 电化学 电化学
- 有机化学 有机化学
- 频谱学是一种光谱学.
背景情况:
- 阿尔法-托科菲罗尔 (alpha-TOH),一种维生素E的形式,是一种重要的抗氧化剂.
- 了解其电化学行为是阐明其生物功能和潜在应用的关键.
- 之前的研究已经探讨了维生素E的氧化还原特性,但其氧化cationic物种的详细表征仍然是一个感兴趣的领域.
研究的目的:
- 为了研究酸中α-托哥菲醇 (α-TOH) 的电化学氧化途径.
- 为了识别和描述由此产生的阴阳性物种,包括阳性阴阳,阴阳基和阴阳性阴阳.
- 在不同的条件下确定这些氧化形式的稳定性和特性.
主要方法:
- 电化学技术:循环电压测量和受控电位电解.
- 在现场的光谱分析:紫外相对NIR,FTIR,EPR和NMR光谱.
- 电化学氧化在乙二中进行,使用Bu(4) NPF(6) 电解质和不同度的三酸 (CF(3) SO(3) H).
主要成果:
- 阿尔法-托科菲罗尔 (alpha-TOH) 通过可逆的两电子/一质子过程在243 K的电化学氧化成稳定的氧离子 (alpha-TO(+)) .
- 在三酸的存在下,α-TO(+) 与α-托科菲罗尔离子基 (α-TOH(+) 存在平衡.
- 在较高的三叶酸度下,alpha-TOH被氧化为alpha-TOH(+) ((*),随后被氧化为alpha-tocopherol分离 (alpha-TOH(2+)).
结论:
- 这项研究成功地描述了α-托哥菲醇 (alpha-TOH) 和其阴离子衍生物的电化学氧化.
- 离子 (alpha-TO(+)) 是一个稳定的中间体,其平衡受酸度的影响.
- 这些发现提供了对α-托科菲罗尔的氧化还原化学的基本见解,这与抗氧化机制和化学合成有关.
相关概念视频
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