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西蒙斯-史密斯反应的反应途径
Masaharu Nakamura1, Atsushi Hirai, Eiichi Nakamura
1Department of Chemistry, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. masaharu@chem.s.u-tokyo.ac.jp
Journal of the American Chemical Society
|February 20, 2003
概括
本研究使用B3LYP计算来研究金属碳化物循环化. 碳化物与基的反应是通过甲转移可行的,在醇反应中观察到加速.
科学领域:
- 计算化学的计算化学
- 有机合成 有机合成
- 有机金属化学 有机金属化学
背景情况:
- 循环化是有机合成中的一个关键反应.
- 金属碳化物,如西蒙斯-史密斯试剂,广泛用于循环化.
- 理解反应机制对于优化合成策略至关重要.
研究的目的:
- 为了阐明金属碳化物循环化反应的反应机制.
- 为了比较和碳化物的反应性.
- 调查与醇的西蒙斯-史密斯反应中的加速机制,并探索二聚体选择性循环化.
主要方法:
- 使用B3LYP混合函数的密度函数理论 (DFT) 计算.
- 反应途径的计算建模,包括甲转移和碳金属化.
- 过渡状态和反应能量学的分析.
主要成果:
- 碳酸迅速经历甲转移和碳金属化.
- 碳化物有利于实验上可行的甲转移途径.
- 对于Simmons-Smith反应与醇的两种加速机制被确定:1,2-迁移和更容易的五中心键交替.
- 对2-环素-1-ol的氧导向环化进行了计算建模,以支持实验观测.
结论:
- 计算研究提供了对金属碳化物循环缩的机械洞察力.
- 这些发现突出了和碳化物之间的反应性差异.
- 这项研究阐明了加速机制,并模拟了二重选择性西蒙斯-史密斯反应,有助于合成设计.
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