在烯酸氧化和氧化反应中的单核非海姆高铁 (III) - 烯酸复合物
Bin Wang1, Yong-Min Lee1, Martin Clémancey2
1Department of Chemistry and Nano Science, Ewha Womans University , Seoul 03760, Korea.
Journal of the American Chemical Society
|January 28, 2016
概括
单核非海姆铁 (III) - 酸复合物有效地以高选择性氧化烯和酸. 这些铁复合物作为强有力的氧化剂,通过O-O键裂变促进碳化合物的氧化.
科学领域:
- 无机化学
- 有机金属化学
- 催化剂
背景情况:
- 非铁复合物在生物无机化学和催化中至关重要.
- 了解高旋铁酸物种的反应性是开发新的氧化催化剂的关键.
- 烯氧化和氧化是有机合成中的基本转化.
研究的目的:
- 合成和表征单核非血高旋铁 (III) - 乙烯复合物.
- 研究这些复合物的催化活性在烯酸环氧化和氧化中.
- 阐明反应机制并确定活性氧化物种.
主要方法:
- 铁酸复合物的合成和光谱表征.
- 使用各种olefins和alkanes的催化研究.
- 运动同位素效应 (KIE) 的测量.
- 立体化学和反选择性分析.
- 使用同位素标记 (H2~18) 的机械研究.
主要成果:
- 在olefin环氧化过程中获得了高的立体,化疗和酶选择性.
- 在环烯环氧化过程中,1. 0的动态同位素效应 (KIE) 表明C=C环氧化比C-H激活更受欢迎.
- 基拉尔铁 (III) - 乙氧复合物产生具有高反选择性的环氧化物,确定乙氧物种为氧化剂.
- 在低温 (-40°C) 时,高区域和立体选择性发生了氧化.
- 机理学研究证实了C-H键的激活是决定速度的,而乙烯氧是酒精产品的来源.
结论:
- 单核非海姆高旋铁 (III) - 氧复合物是碳化合物氧化的强氧化剂.
- 这些复合物在环氧化和氧化反应中具有很高的选择性.
- 铁 (III) - 乙氧物种,而不是铁氧,是活性环氧化剂.
- 该机制涉及O-O键裂变的acylperoxo连接物以产生活性氧化物种.
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