在催化水氨基化中形成协同的C-N和C-H键
James F Dunne1, D Bruce Fulton, Arkady Ellern
1Department of Chemistry and U.S. Department of Energy Ames Laboratory, Iowa State University, Ames, Iowa 50011, United States.
Journal of the American Chemical Society
|December 2, 2010
概括
一个前催化剂促进了分子内胺和循环. 反应通过两基质过渡状态进行,催化剂-基质结合先于限制速率的循环化步骤.
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.
- 有机合成 有机合成
背景情况:
- 内分子胺化是有机合成中的一个关键反应.
- 为此类转型开发高效的前催化剂至关重要.
- 了解反应机制对于催化剂优化至关重要.
研究的目的:
- 为了研究一个协调和复合物的催化活性.
- 为了阐明分子内胺化/循环化的机制.
- 为了确定催化循环中的速度限制步骤.
主要方法:
- 前催化剂To(M) MgMe的合成和表征.
- 动力学研究以确定速率定律和反应顺序.
- 隔离和研究催化剂的静止状态.
- 基于实验观察的机制建议.
主要成果:
- 复合物To(M) MgMe是50°C内分子胺化/循环化的活性前催化剂.
- 反应遵循迈凯利斯-门动力学,表明可逆的催化剂-基质关联.
- 可分离的静止状态 (氨基) 不单分子循环,而是通过基质添加来激活.
- 为周转限制步骤提出了一个两基板,六中心的过渡状态.
结论:
- 催化循环涉及基质与催化剂的初始可逆关联.
- 营业额限制步骤是拟议的六个中心过渡状态内的协调过程.
- 这项研究提供了对催化胺化/循环化反应的机理性见解.
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