11组二甲基酸盐与化酸的气相反应性
Nicole J Rijs1, Naohiko Yoshikai, Eiichi Nakamura
1School of Chemistry, The University of Melbourne, Victoria 3010, Australia.
Journal of the American Chemical Society
|January 28, 2012
概括
硬币金属二甲基甲酸盐, [CH(3) MCH(3) ](-) (M = Cu, Ag, Au),在基替代中的反应性显著不同. 有机在这些反应中表现出色,与银和金相似物不同,原因是它们的反应机制不同.
科学领域:
- 有机金属化学 有机金属化学
- 有机合成 有机合成
- 计算化学计算化学
背景情况:
- 铜介导的基替代反应是已知的合成工具.
- 涉及银和黄金的类似反应在很大程度上是未被探索的.
- 了解机械差异对于合成开发至关重要.
研究的目的:
- 为了研究硬币金属二甲基甲酸盐 ([CH(3) MCH(3) ](-),M = Cu,Ag,Au) 与化的气相反应性.
- 阐明对观察到的反应性趋势负责的潜在反应机制.
- 为了解释有机酸盐在基替代中的优越性能.
主要方法:
- 在近热条件下使用离子陷质谱仪研究气相反应.
- 使用B3LYP/def2-QZVP//B3LYP/SDD6-31+G(d) 理论水平进行的电子结构计算.
- 评估了四种不同的反应机制:S(N) 2,S(N) 2',通过M(III) η(3) -基氧化添加/减少消除 (OA/RE),以及通过M(III) η(1) -基中间体进行OA/RE.
主要成果:
- 有机酸盐 ([CH(3) CuCH(3)](-)) 具有显著的反应性 (6.6%的效率),产生交叉合和同质合产品.
- 器官银 ([CH(3) AgCH(3) ](-)) 和器官黄金 ([CH(3) AuCH(3) ](-)) 的类似物显示出明显较低的反应性和不同的产品分布.
- 计算分析揭示了不同的机制:铜的OA/RE通路占主导地位,银的S(N) 2,黄金没有可行的C-C合.
结论:
- 该研究强调了与银和黄金相比,有机酸盐在基替代反应中的更高功效的机制基础.
- 反应途径依赖于金属,铜有利于氧化-添加/减少消除,银有利于S(N) 2机制.
- 黄金没有动力学上可行的C-C合路径,只形成化物和稳定的Au (III) 复合体.
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