对光学旋转的合规效应. 3-替代的1-丁烯基
Kenneth B Wiberg1, Patrick H Vaccaro, James R Cheeseman
1Department of Chemistry, Yale University, New Haven, Connecticut 067520-8107, USA. kenneth.wiberg@yale.edu
Journal of the American Chemical Society
|February 13, 2003
概括
该研究表明,分子构造显著影响 (R) -(-) -3-chloro-1-butene的光学旋转,计算值在扭转角度之间差异很大. 观察到的旋转小于预测,这表明复杂的因素影响这种现象.
科学领域:
- * 有机化学 有机化学
- * 计算化学 计算机化学
- * 立体化学 立体化学
背景情况:
- * 奇拉性和光学活动在立体化学中至关重要.
- * 了解光学旋转上的构造效应是预测分子性质的关键.
- * (R) -(-) -3-chloro-1-butene作为研究这些关系的模型化合物.
研究的目的:
- * 用于计算和分析 (R) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 的光学旋转.
- * 为了研究C=C-C-C扭矩角度对光学旋转的影响.
- * 将理论计算与实验观测进行比较,并探索替代效应.
主要方法:
- * 光学旋转的理论计算.
- * 基于扭转角度的形状分析.
- * 温度依赖的研究来分析形状平衡.
- * 对光学旋转上的替代效应 (F,CN,CCH) 的理论研究.
主要成果:
- * 计算出光学旋转对C=C-C-C扭矩角度的显著依赖.
- * 适配体之间的自由能量差异被确定为1315cal/mol.
- *观察到的旋转大约比计算值小2.6倍.
- *发现对光学旋转的替换效应是最小的.
结论:
- *分子形状在确定光学旋转方面发挥着关键作用.
- *计算和观察到的旋转之间的差异突显出需要精细的理论模型.
- *替代品对光学旋转的电子效应不如形状效应那么明显.
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