化合物与kappa-P,P,Si (biPSi) 接体:在不和复合体中有利于反应性结构
Eduardo Sola1, Alba García-Camprubí, José L Andrés
1Departamento de Química de Coordinación y Catálisis Homogénea, Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, E-50009 Zaragoza, Spain. sola@unizar.es
Journal of the American Chemical Society
|June 15, 2010
概括
这项研究研究了复合体,揭示了具有不同的协调行为和反应性的两个同位素. 这些差异使选择性插入反应和聚合成为可能,而异构化受到和潜在连接体的影响.
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:
- 研究了具有独特kappa-P,P,Si-Si的五坐标复合体 (Me) (CH) (二) (三) (PPh) (二) (二) 连接体 (biPSi).
- 这些复合物存在于反和同同体的平衡混合物中,其位置偏好受到素和溶剂的影响.
- 两种异构体都采用扭曲的方形基础的金字塔结构,空位转变为.
研究的目的:
- 阐明这些复合物的结构,协调特性,插入过程和动态行为.
- 为了了解抗和同同异构体之间的反应性差异.
- 探索异构和插入反应的机制.
主要方法:
- 复合物的结构特征.
- 用光谱学研究 (NMR) 来监测同位素平衡和反应.
- 协调和插入过程的动力学和热力学分析.
- 计算研究 (MP2计算) 支持机械学建议.
主要成果:
- 同性异构体很容易形成六坐标 adducts,而抗异构体显示有限的协调.
- 插入试剂选择性地与同位素的Ir-H键反应,从而产生基或基产物.
- 乙烯聚合发生在syn同位素的协调球体内.
- 反异构体异构化成合成产物,其速率取决于插入反应剂和H2度.
- 一种拟议的异构化机制涉及Ir(V) 中间体和一个毒性过渡状态.
结论:
- 抗和同异构体之间的结构细微差别决定了协调和反应性的显著差异.
- 合成同位素对于选择性插入反应和乙烯聚合是至关重要的.
- 异构化途径受到外部因素的影响,提出的一种机制涉及毒性相互作用.
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