富含电子的N-异环烯 (NHSi) - 铁复合物:可分离的二烯 - 铁复合物的合成,结构和催化能力
Burgert Blom1, Stephan Enthaler, Shigeyoshi Inoue
1Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin, Strasse des 17. Juni 135, Sekr. C2, D-10623 Berlin, Germany.
Journal of the American Chemical Society
|April 11, 2013
概括
研究人员报告了第一个富含电子的N-异环烯 (NHSi) -铁 (0) 复合体. 这些复合物,包括一种罕见的Si(II) 化物,在基化中表现出催化活性,证明了对基催化剂的新型反应性.
科学领域:
- 有机金属化学 有机金属化学
- 主群 化学 化学
- 催化剂是一种催化剂.
背景情况:
- N-异环烯 (NHSi) 是协调化学中的多功能联体.
- 铁(0) 复合体为催化应用提供独特的电子特性.
- 二) 种通常具有反应性,难以分离,特别是在过渡金属复合体中.
研究的目的:
- 合成和表征新型富含电子的N-异环烯 (NHSi) - 铁(0) 复合物.
- 研究这些独特的Si (II) -Fe (0) 系统的结合和电子结构.
- 在有机转化中探索Si (II) 化物复合物的催化潜力.
主要方法:
- 通过Fe(0) 前体与N- heterocyclic chlorosilylene的反应合成铁复合物.
- 使用光谱方法 (NMR,IR等) 进行表征. 和单晶X射线衍射.
- 使用密度函数理论 (DFT) 分析结合和反应机制的计算研究.
主要成果:
- 首个富含电子的NHSi-铁(0) 复合物的分离和表征,包括一个稳定的Si(II) 化物复合物.
- DFT计算揭示了Si (II) 和Fe (0) 中心之间显著的多重结合特征.
- 化复合物在酸的水化中表现出催化活性,产生具有高转化率的酒精.
结论:
- 这些新型NHSi-铁复合物的成功合成和表征扩大了低价值化学的范围.
- 二) 化物复合物是水化反应的罕见且有价值的前催化剂.
- 该研究提供了对催化循环的机械洞察力,涉及一个关键的化物转移步骤和一个化中间体.
相关概念视频
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