灵活的N-异环碳素:IMes和IPr之间的非对称连接
Qun Zhao1,2, Mahbubur Rahman1, Tongliang Zhou1
1Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
Angewandte Chemie (International ed. in English)
|December 22, 2023
概括
研究人员开发了具有可旋转翼尖的新型非对称的N-异环碳联体,扩大了超越IMes和IPr的催化口袋几何. 这些配体在铜催化β-化中表现出高反应性,用于合成化合物.
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.
- 合成化学 合成化学
背景情况:
- 像IMes和IPr这样的N-异环碳化合物 (NHC) 在均质催化中被广泛使用.
- 目前的NHC配体缺乏固态灵活性,限制了催化口袋设计.
- 需要具有可调节的固态环境的NHC连接体.
研究的目的:
- 引入一种新的类别的非对称的NHC配体与自由旋转的N-芳香翼尖.
- 探索新的连接物拓和现有NHC无法访问的硬质环境.
- 为了研究这些连接体在铜催化β-氧化中的应用.
主要方法:
- 不对称的N-异环碳联体的合成,具有可旋转的N-CH2Ar键和一个结构固定的N-Ar链接.
- 在铜 (I) 催化β-化反应中对联体性能的评估.
- 使用%Vbur (形角度) 量化固态参数.
主要成果:
- 新的NHC连接体表现出模块化拓,并访问独特的几何形状.
- 干体在Cu(I) 催化β-化中表现出高反应性,这是一个关键的化过程.
- 硬质散体 (%Vbur) 范围从37.3%到52.7%,后者是IPr同类产品中最大的.
- 最具反应性的配体已经商业化.
结论:
- 这种新的连接体设计在NHC催化中提供了前所未有的模块化和固态控制.
- 开发的配体为含化合物提供了新的合成途径.
- 这项工作有望推进有机合成,药物发现和金属中心稳定.
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