对立体合作催化物的绝对和相对立体控制的见解
Avtar Changotra1, Bangaru Bhaskararao1, Christopher M Hadad2
1Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
Journal of the American Chemical Society
|May 7, 2020
概括
在非对称催化过程中,使用两个兼容的性催化剂,可以同时控制绝对和相对的配置. 这项研究表明,催化剂之间的非共价相互作用决定了反应的立体分离,使得所有产品的立体同位素都可获得.
科学领域:
- 有机化学
- 催化剂
- 计算化学
背景情况:
- 在不对称催化过程中,同时控制绝对和相对配置是一个重大挑战.
- 使用多种催化剂以获得不同的立体化学结果的立体分离催化是快速发展的领域.
- 了解基质激活和选择性的起源对于设计有效的催化系统至关重要.
研究的目的:
- 研究两种过渡金属复合物催化反应中的立体分离的分子起源.
- 阐明不同性催化剂的组合如何影响所有四种立体同位素的形成.
- 在单,双催化剂系统中确定控制立体选择性的关键因素.
主要方法:
- 使用B3LYP-D3函数的密度函数理论 (DFT) 计算.
- 这项研究重点是阿扎利乙胺与肉甲基碳酸盐之间的反应.
- 对过渡状态中的非共价相互作用 (NCIs) 进行了分析,以了解立体控制.
主要成果:
- 该产品的四个立体同位素均具有两个连续立体中心,可以通过不同的催化剂组合获得.
- 立体差异的起源归因于催化剂之间的非共价相互作用的数量和类型的差异.
- 特定的NCIs,如C-H··π,C-H··F和π··π相互作用,被确定为过渡状态中的关键差异化因素.
结论:
- 合金铜-瓦尔和-胺催化剂的组合可实现精确的立体化学控制.
- 性催化剂之间的非共价相互作用在确定立体差异化过渡状态的能量方面发挥着关键作用.
- 这些发现为设计高级立体分离催化剂框架提供了分子见解.
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