在不和Rh复合体的联体中发生意想不到的同质化:结合实验和理论
Niroshani S Abeynayake1, Nghia Le1, Gabriela Sanchez-Lecuona1
1Department of Chemistry, Mississippi State University, Box 9573, Mississippi State, Mississippi 39762, USA. ewebster@chemistry.msstate.edu.
Dalton transactions (Cambridge, England : 2003)
|October 25, 2023
概括
这项研究研究了-酸连接体复合体,详细说明了原子上的替代物如何影响单体-二元平衡. 研究表明,固体体积决定了产品的形成,在化学中,较大的群体偏爱单体,较小的群体偏爱二体.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 合金复合物 合金复合物
背景情况:
- [RhCl (COD) ]2与基PHP (o-C6H4CH2SiHiPr2) 2 (L1) 的反应产生了单体和二体复合体.
- 基替代剂在联体原子上的固态质量在确定产品分布方面起着至关重要的作用.
研究的目的:
- 为了研究单体和二元复合物的形成与特定的素连接体.
- 了解不同基替代剂对联体的原子对单体-二元平衡的影响.
- 阐明观察到的复合物的形成机制.
主要方法:
- 综合复合物 ([RhCl(COD) ]2与益质体L1) 的合成.
- 主要 (Rh-1) 和次要 (Rh-3) 产品的表征.
- 计算研究分析单体二元平衡和反应机制.
- 在水的存在下通过C-H激活对副产品形成 (Rh-4) 的研究.
主要成果:
- 主要产物是单质的14电子的Rh(III) 复合物[ClRh(κ(P,Si,Si) PhP(o-C6H4CH2SiHiPr2) 2) ] (Rh-1).
- 二次复合物[μ-Cl) Rh-κ,P,Si,Si) PhP,C6H4CH2SiPr2 ,C6H4CH2SiPrnPr) 2 (Rh-3) 是一个次要的产物,受到较小的替代品的青.
- 计算分析证实,增加的固体体积 (四个异基团) 有利于单体,而减少的体积 (一个n-基团) 有利于二元体.
- 直接从[RhCl(COD) ]2形成Rh-3在能量方面比从Rh-1形成更受青.
- 一个Si-O-Si桥接复合体 (Rh-4) 由Rh-1与水反应而形成,涉及分子内C-H激活.
结论:
- 这些复合体中的单体二元平衡对联体替代物的固体性质非常敏感.
- 绝缘阻碍是控制溶液中复合物的物种化的一个关键因素.
- 在偶然的水的存在下,分子内C-H激活可以导致意外的复杂结构的形成.
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