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通过扭曲三平台进行P-N合作性激活和催化化
Yi-Chun Lin1, Emmanuel Hatzakis2, Sean M McCarthy
1Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|April 12, 2017
概括
这项研究详细介绍了一种使用三胺和皮纳 (HBpin) 的新型催化化. P-N 合作机制使转化效率高,可再生催化剂进行进一步的反应.
科学领域:
- 有机化学
- 催化剂
- 有机合成
背景情况:
- 三胺是合成化学中的多功能试剂.
- 化是功能化不和化合物的关键转化.
- 开发高效的催化系统仍然是一个活跃的研究领域.
研究的目的:
- 为了研究几何约束三胺与皮纳科尔博兰 (HBpin) 的固体测量和催化反应性.
- 阐明B-H键激活的机制和随后的催化化.
- 为观察到的催化活性建立P-N合作机制.
主要方法:
- 使用NMR光谱测定反应速率和速率规律的动态研究.
- 关键中间体的独立合成和表征.
- 使用三胺和HBpin的各种imine基质的催化化.
主要成果:
- 添加HBpin到三胺会导致合作性B-H键裂变.
- 形成了P- 基-1,3,2- 酸中间体,表现出基反应性.
- 用三胺作为催化剂和HBpin作为源实现了对伊米因的催化.
- 反应动力学遵循B-H激活的二次速率定律和中间分解的第一阶速率定律.
结论:
- 已经提出了P-N合作机制,用于催化 imines 的化,并得到了实验证据的支持.
- 具有几何限制的三化物作为一种有效的催化剂.
- 这项工作提供了有关基系统在合作催化中的反应性的见解.
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