通过可逆原子转移在sp3混合碳中心进行光化学脱血
Johannes Großkopf1, Manuel Plaza1, Antonia Seitz1
1School of Natural Sciences, Department Chemie, and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany.
Journal of the American Chemical Society
|December 13, 2021
概括
这项研究引入了一种新的光化学脱血方法, 该方法通过选择性原子转移实现高反选择性,丰富一个产品反体.
科学领域:
- 有机化学
- 摄影化学
- 不对称的合成
背景情况:
- 氨酸是重要的异环化合物,具有多种应用.
- 在制药和材料科学中,获得纯净化合物至关重要.
- 光化学方法为分子转化提供了独特的途径.
研究的目的:
- 开发一种新的光化学脱血方法,
- 为了研究原子转移的机制.
- 在脱血过程中获得高产量和度 (ee).
主要方法:
- 使用性二甲基催化剂进行光化学反应.
- 详细的机械研究包括DFT计算,激进时钟实验和H/D标签.
- 使用奇拉色谱分析基质转化和酶体过量.
主要成果:
- 成功脱血了27个5-替代的3-利米达二,4- (hydantoins) 的样本.
- 获得高产量 (69%量) 和优异的抗选择性 (80-99% ee).
- 建立了一种涉及选择性原子转移 (HAT) 的机制,从一个基质反体转移到光激发的催化剂.
结论:
- 开发的光化学脱血是一种有效的方法来获取纯化素.
- 性二甲基催化剂通过结和HAT有效地区分基质.
- 由于其对催化剂的惰性性,光静态状态丰富了所需的产品反体.
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