σ-环基到π-基重排在Au的位置
Marte S M Holmsen1,2,3, David Vesseur1, Yago García-Rodeja4
1CNRS/Université Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062, Toulouse Cedex 09, France.
Angewandte Chemie (International ed. in English)
|June 6, 2023
概括
黄金 (III) 环基复合物可以通过环开放转化为π-基复合物. 这种反应即使在低温下也很快发生,这取决于附属连接物附着在黄金中心.
科学领域:
- 有机金属化学 有机金属化学
- 黄金催化剂的使用方法
- 反应机制 反应机制
背景情况:
- 黄金 (III) 复合物以其多样化的反应性而闻名.
- 环基团可以在有机金属化学中充当连接体.
- 了解连接体转换对于催化剂的发展至关重要.
研究的目的:
- 为了研究黄金(III) σ-cyclopropyl复合物的环开放.
- 从这些前体中确定π-基复合物的形成.
- 探索辅助连接体对这种转换的影响.
主要方法:
- 金的合成和表征 (III) σ-cyclopropyl复合物.
- 改变温度的动力学研究,以监测转变.
- 密度函数理论 (DFT) 和内在键轨道 (IBO) 分析以阐明反应机制.
主要成果:
- 在 -50°C下,在几个小时内观察到 (P,C) 循环金属化黄金(III) σ-cyclopropyl复合物到π-allyl复合物的环开放.
- 这种转化被推广到其他辅助联体,反应速率因联体类型而异 (例如, (N,C) 和 (P,N) 复合体).
- DFT的计算证实了无旋转电环开放机制,并得到了IBO分析的支持,显示了σ(CC) 键裂解和π-基形成.
结论:
- 黄金(III) σ-cyclopropyl复合物很容易经历环开放,形成π-合物复合物.
- 反应速率可以通过选择辅助配体来调整.
- 该机制涉及电循环环开放,在阴阳金 (III) 环烯基复合体中可能存在C-C杂态相互作用.
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