催化化:对手控制的区域选择性
Xiao-Hui Yang1, Ryan T Davison1, Shao-Zhen Nie1,2
1Department of Chemistry , University of California , Irvine , California 92697 , United States.
Journal of the American Chemical Society
|February 9, 2019
概括
这项研究详细介绍了dienes的催化化,控制了与罗 counterions 的区域选择性. 这种方法使得从β-farnesene中首次能够对 (-) - agelasidine A进行enantioselective合成.
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:
- 1,3-二烯的催化硫化对于合成和同硫化物至关重要.
- 在这些反应中控制区域选择性仍然是一个重大挑战.
研究的目的:
- 为了扩展1,3-二烯的催化化.
- 为了达到高的区域控制,在形成化或同化硫化物.
- 为了使第一个enantioselective合成的 (-) - agelasidine A.
主要方法:
- 使用了具有不同 counterions (例如,SbF6-, Cl-) 的 (Rh) 复合体.
- 研究了涉及不同基因协调模式 (η4 vs. η2) 的机械路径.
- 进行了精油成分β-farnesene的基化.
主要成果:
- 区域选择性是由Rh对象决定的:非协调对象倾向于酸硫化物 (η4协调),而协调对象倾向于同质酸硫化物 (η2协调).
- 为马尔科夫尼科夫和反马尔科夫尼科夫路径合理化分数和反向醇依赖的拟议机制.
- 成功合成了 (-) - - agelasidine A 通过对抗选择性.
结论:
- 选择的 counterion 是一个关键的决定因素,为 regioselectivity 在Rh-催化 1,3-dienes 的水合硫化.
- 开发了一种机理性理解不同基解路径中的醇依赖性.
- 建立了一个新的路径,用于 (-) - agelasidine A. 的 enantioselective 合成.
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