DFT 研究铁中因胺交换反应的研究 (II) - 协调器
Annemieke van Dam1, Robin van Schendel1, Satesh Gangarapu1
1Laboratory of Organic Chemistry, Wageningen University, Stippeneng 4, 6708WE, Wageningen, The Netherlands.
Chemistry (Weinheim an der Bergstrasse, Germany)
|August 10, 2023
概括
金属协调催化 imine 交换反应. 这项研究发现,虽然Fe2+协调降低了激活能量,但外部氨基酸对于自发的氨基酸凝聚和转氨基酸反应至关重要.
科学领域:
- 动态共价化学 动态共价化学
- 有机金属化学 有机金属化学
- 计算化学的计算化学
背景情况:
- 胺基键是动态共价化学中的关键,通常由金属协调稳定.
- 对胺交换反应的机理研究在很大程度上忽视了金属协调的作用.
研究的目的:
- 为了研究Fe2+协调对imine凝结和transimination反应的机械效应.
- 探索金属离子和氨基添加剂在氨基交换动力学中的作用.
主要方法:
- 密度函数理论 (DFT) 计算 (wB97XD/6-311G(2d,2p)) 在亚二中.
- 实验证实了Fe2+对二胺胺的协调作用.
- 过渡状态和激活能量对凝结和转光的分析.
主要成果:
- 与非协调的系统相比,Fe2+协调显著降低了 imine 交换的激活能量.
- 添加乙胺分子大大降低了能量障碍,使自发反应成为可能.
- 氨基和子替代剂的性质对激活能量的影响最小.
结论:
- 金属协调,特别是与Fe2+,作为胺基交换反应的催化剂.
- 外部氨基度对于实现实验观察到的反应速率至关重要.
- 这项工作强调了在动态共价化学的机理学研究中考虑金属协调的重要性.
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