合成,结构,理论研究,和单质的,T形的烯二化合物复合物的连接交换反应,T形的烯二化合物复合物与额外的,微弱的毒体相互作用
James P Stambuli1, Christopher D Incarvito, Michael Bühl
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society
|January 30, 2004
概括
研究人员使用重的氨酸配体合成了单体烯 (Arylpalladium) 复合物. 这些复合体,具有一个联体转换到一个开放的网站,显示潜在的稳定通过光学相互作用,与键强度受联体性质的影响.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂研究研究
- 协调化学 协调化学
背景情况:
- 复合物在催化过程中至关重要.
- 了解烯 (Arylpalladium) 复合物的结构和反应性是开发新合成方法的关键.
- 大量的胺联体显著影响复合物的特性.
研究的目的:
- 准备和表征新型单体甲 (Arylpalladium) 复合物.
- 为了研究化和三酸盐与前体的氧化添加反应.
- 探索合成复合物的结构特征和电子特性.
主要方法:
- 合成单体甲 (Arylpalladium) 复合物 (LPd) (Ph) X) 使用庞大的素配体 (L = 1-AdPtBu2, PtBu3, Q-phos) 和各种对应物 (X = Br, I, OTf).
- 氧化添加反应涉及(0) 前体和化,化,化或三酸盐.
- 使用X射线衍射和密度函数理论 (DFT) 计算的复合体的表征.
主要成果:
- 通过氧化添加化和化,成功制备了单质的化 (Arylpalladium) 复合物,取得了良好的产量.
- 在类似条件下观察到化和三酸的无效氧化添加.
- X射线衍射揭示了T形单体结构与联体转向一个开放的协调部位.
- DFT的计算表明通过弱的敏电相互作用实现稳定,而Pd-H键强度取决于连接体的电子性质.
- 氧化添加率各不相同,与Pd(Q-phos) 2相比,Pd(1-AdPtBu2) 2和Pd(PtBu3) 2. 2表现出更快的反应.
结论:
- 单体烯 ((II) 复合物可以有效地使用特定的大型氨酸联体和烯化物合成.
- 氧化添加中的反应性对烯化物和素连接体的性质敏感.
- 这种T形几何形状和敏度相互作用在这些复合物的稳定性中起着重要作用.
- 连接体的电子性质对于调节阿里巴拉 (II) 复合体中的光学相互作用强度至关重要.
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The word polymer is derived from the Greek words “poly” which means “many” and “mer” which means “parts”. Polymers are long chains of molecules composed of repeating units of smaller molecules, known as monomers. They either occur naturally, such as DNA and proteins, or can be constructed synthetically, like plastics. They have varied structural characteristics, such as linear chains, branched chains, or complex networks, that contribute to the properties that they exhibit. Additionally,...


