氧化诱导的C ((sp3) -C ((sp3) 键的形成在一个被塞进来的铁中 (iii) 复合体
Joseph A Zurakowski1,2, Connor S Durfy1, Noah B Stocek3
1Department of Chemistry, Western University 1151 Richmond Street London ON N8K 3G6 Canada marcus.drover@uwo.ca.
Chemical science
|July 12, 2024
概括
铁复合物的单电子氧化触发了C(sp3) -C(sp3) 键的形成,产生了独特的铁二极体. 这项研究揭示了金属碳键强度和化学合成中的碳化合物应变效应的洞察力.
科学领域:
- 有机金属化学 有机金属化学
- 合成化学 合成化学
- 计算化学的计算化学
背景情况:
- 在合成化学中,碳-碳键的形成至关重要,通常通过过渡金属催化交叉合反应来实现.
- 了解金属氧化状态,碳化合物应变和金属碳键热化学之间的关系是开发新合成方法的关键.
- 铁复合体为探索基本反应性和键激活过程提供了一个平台.
研究的目的:
- 为了研究一种特定的铁复合体在一电子氧化后的反应性.
- 阐明铁复合体中C(sp3) -C(sp3) 键形成的机制.
- 为了将金属-碳键解离能 (BDE) 与碳化合物应变和反应性相关联.
主要方法:
- 铁复合物的合成和表征,包括[η6-C5Me4-CH2) Fe[dnppe]和[Cp*Fe[dnppe]CH3]+.
- 电化学氧化和冷灭CW X波段EPR光谱,以确定反应中间体.
- 密度函数理论 (DFT) 计算以确定键解离能和电子结构.
主要成果:
- [η6-C5Me4-CH2) Fe的单电子氧化导致了C(sp3) -C(sp3) 键的形成,产生了独特的{Fe2}二元体.
- 作为主要以Fe为中心的基质,对反应性[η6-C5Me4-CH2) Fe[dNppe) ]+中间体进行光谱鉴定.
- DFT计算显示中间体中的Fe-C键较弱 (BDE = 24.5 kcal mol-1),与相似的Fe (III) 甲基复合物中的更强键 (BDE = 47.8 kcal mol-1) 相反.
结论:
- 该研究表明,单电子氧化可以诱导特定铁复合体中的C(sp3) -C(sp3) 合,这种合是由金属-碳键减弱所促进的.
- 观察到的反应性与基中C-C键解离能量的压力诱导下降相似,与乙相比.
- 这些发现为控制金属-碳键激活和C-C键形成在有机金属化学中的因素提供了宝贵的见解.
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