不被激活的末端和内部烯酸与三甲基替代烯酸的线性选择性利化
Joseph S Bair1, York Schramm, Alexey G Sergeev
1Division of Chemical Sciences, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|August 30, 2014
概括
这项研究引入了一种新的水利化方法,用于从未激活的烯和三甲基替代烯中产生线性烯. 反应具有很高的选择性,由一个独特的催化机制驱动,包括可逆的中间体形成和速率决定的减少性消除.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 有机金属化学 有机金属化学
背景情况:
- 水利化反应对于合成基烯化合物至关重要.
- 导向组通常需要在未激活的烯酸的水利化中具有很高的选择性.
- 现有的方法往往缺乏效率或选择性,对具有挑战性的基质.
研究的目的:
- 用三甲基替代的烯来开发未激活的烯的选择性化.
- 调查反应机制,包括中间形成和速率决定步骤.
- 为了实现对线性基烯产品的高选择性,而不需要指导组.
主要方法:
- 使用催化剂用于水利化反应.
- 采用实验力学研究,包括标记实验.
- 使用密度函数理论 (DFT) 进行计算研究.
主要成果:
- 对线性水利化产品与未激活的烯和三甲基替代烯实现了高选择性.
- 证明了内部,非循环烯的成功化,产生线性烯产物.
- 确定了可逆形成的基尼克尔-基中间体和速率决定的还原性消除作为关键的机制特征.
- 展示了从内部基中形成终端基烯的过程涉及初始基异构化.
- 计算研究支持了关于C-H债券转移和速率决定的减小消除的实验发现,形成了反马尔科夫尼科夫产品.
结论:
- 开发了一种多功能且高度选择性的未被激活的烯酸的催化化.
- 阐明了一种新型的催化机制,包括异构化和还原性淘汰.
- 由于异构化,反应对α-olefin度的逆顺序依赖是其催化效率的关键.
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