四坐标合金具复合体:通过同解和异解路径进行电子结构研究和联结物修饰
Scott P Semproni1, Carsten Milsmann, Paul J Chirik
1Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|June 5, 2014
概括
钉复合物通过原子抽象进行修改,形成新的复合物. 这种反应性受到连接体和金属的影响,在复合体中产生较弱的C-H键.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 催化剂是一种催化剂.
背景情况:
- 在有机金属化学中,子连接体至关重要,提供独特的协调环境.
- 由于其可访问的氧化还原状态和催化潜力,复合物引起了人们的兴趣.
- 了解连接体修饰是设计新催化系统的关键.
研究的目的:
- 为了合成和表征复合物与三丁替代 bis ((phosphino) pyridine 链接剂.
- 为了研究这些复杂物对原子抽象的反应性.
- 评估这些系统中的电子结构和C-H键强度.
主要方法:
- 合成和结构性表征的钉复合物.
- 复合物的反应与原子抽象研究的TEMPO基.
- 热解实验以评估连接物修饰.
- 原子交换实验用于确定C-H键强度.
- 电子偏磁共振 (EPR) 光谱和密度函数理论 (DFT) 计算用于电子结构分析.
主要成果:
- 成功合成复合物与完整的和修改的链体.
- 通过TEMPO证明了从基位置抽取原子,产生修饰复合物.
- 在甲基和化复合物中,热解诱导了器修饰,而化和乙化复合物是惰性的.
- 建立了X型联体标识和基C-H键强度之间的相关性, σ-捐赠者削弱了键.
- 电子结构分析揭示了修改复合体中的低旋转Co (II) 配置.
结论:
- 科巴尔特具复合体可以通过原子抽象很容易地被修改,受辅助连接体的影响.
- 中心的电子特性,特别是其氧化还原活性,显著影响远程的C-H键强度.
- 这些发现提供了对可调节反应率的基催化剂设计的见解.
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