溶解的pi面选择性可以通过原子模拟来预测吗?
Roberto Berardi1, Gianfranco Cainelli, Paola Galletti
1Dipartimento di Chimica Fisica e Inorganica and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, Università di Bologna, Viale Risorgimento 4, 40136 Bologna, Italy.
Journal of the American Chemical Society
|July 28, 2005
概括
这项研究预测了使用分子动力学模拟的核性添加物中性溶剂效应. 模拟可以准确预测反转温度,进步对立体选择反应的理解.
科学领域:
- 立体选择性有机合成
- 计算化学是一种计算化学.
- 物理有机化学 有机化学
背景情况:
- 核性添加到奇拉性碳烯化合物对于合成性纯分子至关重要.
- 溶剂和温度在这些反应中显著影响了面部异质选择性.
- 了解这些影响是控制立体化学结果的关键.
研究的目的:
- 为了合理化和预测溶剂和温度对面部异质选择性的影响,在核爱性添加到α-奇拉碳烯化合物中.
- 在不同的溶剂和温度下研究 (R) -2--甲的面部溶解.
- 在立体选择性反应中开发逆转温度的预测模型.
主要方法:
- 用分子动力学 (MD) 模拟来研究 (R) -2--甲的面部溶解.
- 模拟在n-pentane和n-octane中进行了各种温度的模拟.
- 结果与来自nBuLi加法和非线性Eyring图的实验 diastereoselectivity数据进行了比较.
主要成果:
- 观察到面部溶解模式随着温度和使用的烯溶剂而变化.
- 引入了分子性指数,以预测温度依赖的效应.
- 预测的断裂温度 (T(CI)) 与实验观察到的反转温度 (在20度范围内) 非常接近.
结论:
- 分子动力学模拟为立体选择性反应中的溶剂和温度效应提供了宝贵的见解.
- 开发的分子性指数为预测反转温度提供了一种可行的方法.
- 这种方法对预测各种立体选择反应中微妙的溶剂效应具有前景.
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