基离子分散促进未激活的氨酸的铜催化胺化
Gang Lu1, Richard Y Liu2, Yang Yang2
1Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States.
Journal of the American Chemical Society
|October 25, 2017
概括
研究人员发现,配体和基质之间的吸引力分散相互作用增强了铜催化胺反应的反应性. 具有P- 基的大型素配体是这种改善催化性能的关键.
科学领域:
- 有机金属化学
- 催化剂
- 计算化学
背景情况:
- 过渡金属催化中的联体效应通常由通过键和通过空间的相互作用解释,后者通常被视为排斥性.
- 在过渡金属催化中很少考虑吸引力非共价相互作用,例如连接体和基质之间的分散力.
- 了解这些相互作用对于设计更有效的催化剂至关重要.
研究的目的:
- 为量化评估催化剂-基质相互作用开发一个计算模型.
- 在化铜 (CuH) 催化水氨酸中研究连体-基质分散相互作用的作用.
- 为了阐明体积较大的双酸配体所观察到的增强反应性的来源.
主要方法:
- 分析催化剂-基质相互作用的计算模型的开发.
- 该模型应用于未激活的氨酸的铜化催化.
- 通过使用各种素配体的动力学研究进行验证.
主要成果:
- 计算模型对催化剂-基质相互作用进行了定量分析.
- 在CuH催化水氨基化中,增强的反应性源于具有吸引力的配体-基质分散相互作用.
- 大量的双酸连体,特别是具有P- 基的酸连体,显著提高反应速率.
结论:
- 分散相互作用在过渡金属催化中起着关键的,但经常被忽视的作用.
- 在CuH催化水氨基化中,大型素配体的增强性能归因于有利的配体-基质分散力.
- 结合庞大的P-aryl组的配体的战略设计可以优化催化效率.
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