萨拉伦催化 选择性基氧化
Christina Wartmann1, Shiny Nandi1, Jörg-Martin Neudörfl1
1Department of Chemistry, Organic Chemistry, University of Cologne, Greinstraße 4, 50939, Cologne, Germany.
Angewandte Chemie (International ed. in English)
|June 27, 2023
概括
一种新型的催化剂有效地进行了基C-H键的不对称氧化和使用过氧化氧化的烯酸氧化. 这种催化剂实现了高的enantioselectivity,在催化化学方面取得了重大进展.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 有机合成 有机合成
背景情况:
- 伯克塞尔-卡茨库基催化剂是一种复合物,含有cis-1,2-diaminocyclohexane (cis-DACH) 衍生的伯克塞尔-萨拉伦连接体,以高效的不对称环氧化而闻名.
- 基C-H键的不对称的催化氧化仍然是合成化学的一个挑战.
研究的目的:
- 调查伯克塞尔-卡茨库基催化剂对于非对称基基化C-H的潜力.
- 开发一种优化的催化剂,以增强酶选择性氧化和环氧化反应.
主要方法:
- 基于机制的伯克塞尔-萨拉伦连接体的连接体优化.
- 使用过氧化对终端烯酸的不对称环氧化.
- 使用过氧化进行基C-H键的不对称氧化.
主要成果:
- 开发的酸盐Ti-催化剂在不对称的催化基化中表现出报告的最高效率,达到高达98%的异构分子过量 (ee).
- 对子副产品的过氧化是最小的.
- 这种新型催化剂还证明了增强的环氧化效率,在低催化剂负荷 (0.1 mol-%) 的情况下,将1 - 十烯转化为其环氧化物,产量为90%,EE为94%.
结论:
- 新型酸盐Ti-催化剂对于不对称的基酸C-H氧化和烯酸烯酸环氧化都非常有效.
- 这种催化剂代表了选择性催化剂的重大进步,在有机合成中具有广泛的适用性.
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