原子的热力学转移到一个高价值铁模拟复合体
Ismael Nieto1, Feizhi Ding, Ranko P Bontchev
1Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces New Mexico 88003, USA.
Journal of the American Chemical Society
|February 13, 2008
概括
高价值的铁模态复合物促进了原子的转移. 研究人员确定了一种特定的铁模态复合物的N-H键解离能,揭示了其在原子转移反应中的反应性.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 反应机制 反应机制
背景情况:
- 高价值的铁模态复合物是各种催化转化中的关键中间体.
- 了解它们的反应性,特别是原子转移 (HAT) 能力,对于设计新的催化剂至关重要.
- 热力学数据为反应途径和可行性提供了基本的见解.
研究的目的:
- 为了研究高价值铁的热力学性质,高价值铁的imido复合物[LMesFe[三键]NAd]OTf.
- 为了确定这个复杂的原子转移 (HAT) 潜力.
- 为了将热力学数据与观察到的反应性相关联.
主要方法:
- 使用循环电压测量来评估铁模复合物的氧化还原特性.
- 使用实验和计算研究的组合来确定质子复合物的酸度.
- 热力学循环是用来计算键解离能量的.
主要成果:
- 发现铁模复合物氧化能力较弱 (E1/2 = -0.98 V 与 MeCN 中的 Cp2Fe+/Cp2Fe 相比).
- 在MeCN中,LMesFe-N(H) Ad+的酸度被确定为pKa = 37.
- 据计算,N-H键解离能 (BDE) 是88(5) kcal/mol.
- 该复合物与9,10-二甲烯 (C-H BDE = 78(1) kcal/mol) 反应,产生甲烯,与计算的N-H BDE一致.
结论:
- 热力学数据支持铁复合体在原子转移反应中的作用.
- 计算的N-H BDE表明对HAT的倾向,使9,10-二甲等基质的氧化成为可能.
- 这项研究提供了有价值的热力学参数,以了解HAT过程中高价值铁像素复合物的反应性.
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