对斯图丁格反应的扭矩选择性的新见解
Yong Liang1, Lei Jiao, Shiwei Zhang
1Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Journal of the American Chemical Society
|January 10, 2009
概括
斯劳丁格反应出乎意料地形成了扭力电子不利的产物. 伊米因的电子性质影响产物比率,挑战了Staudinger反应中简单的扭矩电子预测.
科学领域:
- 有机化学 有机化学
- 反应机制 反应机制
- 计算化学计算化学
背景情况:
- 斯劳丁格反应是合成β-乳酸的一个关键方法.
- 了解立体化学结果,如扭力选择性,对于合成控制至关重要.
- 以前的模型没有完全解释与非对称反应物的反应中的立体选择性.
研究的目的:
- 为了研究控制斯图丁格反应的扭矩选择性和电子效应.
- 探索电子产品特性对产品分销的影响.
- 为了比较Staudinger反应中的扭矩电子控制与其他循环反应.
主要方法:
- 使用非对称循环基和循环伊对施陶丁格反应进行实验研究.
- 密度函数理论 (DFT) 计算以建模反应路径.
- 哈梅特分析将电子效应与产品比率相关联.
- 动力竞争实验,以确定速度决定的步骤.
主要成果:
- 首次观察到扭力电子不利的供体β-lactams的主要形成.
- 通过哈梅特分析,确定了imine电子性质和捐赠者/捐赠者产品比率之间的明确关系.
- DFT和动力数据显示了捐赠者进入和捐赠者退出途径的不同率决定步骤.
结论:
- 施陶丁格反应中的扭矩电子控制与环开环反应有很大不同.
- 斯图丁格反应与非对称基因的二重选择性不仅仅是扭矩电子模型可以预测的.
- 伊米因的电子效应在指导斯图丁格反应的立体化学结果方面发挥着至关重要的作用.
相关概念视频
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