氨酸的反热力学定位异构
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|December 30, 2021
概括
这项研究引入了一种新型光驱的烯酸异构法,将稳定的烯酸转化为不稳定的异构物. 这一过程利用光反氧催化和共催化剂来实现反热力学转换.
科学领域:
- 有机化学
- 摄影化学
- 催化剂
背景情况:
- 在有机合成中,素异构是至关重要的.
- 实现反热力学同质化,特别是对更多替代的烯,仍然具有挑战性.
- 现有的方法往往缺乏效率或基质范围.
研究的目的:
- 开发一种以光驱动的方法来对抗热力学定位异构化烯酸.
- 为了使热力学稳定性较差的同体的合成.
- 扩大素异构反应的基质范围.
主要方法:
- 阶段性质子合电子转移 (PCET) 激活烯基基底.
- 使用激发状态氧化剂和布伦斯特德基.
- 使用Cr (II) 联合催化剂形成 (III) 中间体.
- 使用甲醇进行区域选择性原化.
主要成果:
- 成功的光驱,反热力学定位异构化烯酸.
- 形成和捕获一个基中间体.
- 热力学稳定性较低的基产物的高度区域选择性合成.
- 已证明的基质范围包括乙烯,乳,烯,1,3-烯和四基替代烯.
- 由于其惰性的原因,较少被替代,较不稳定的olefin异构体的积累.
结论:
- 开发的方法提供了有效的热力学不利的烯异构体.
- 光反催化方法为氨酸功能化提供了多功能平台.
- 获得了对原始化步骤的机械洞察力.
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