在奇拉识别中使用电子不对称.
Seth N Brown1, Everett T Chu, Michael W Hull
1Department of Chemistry and Biochemistry, 251 Nieuwland Science Hall, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. Seth.N.Brown.114@nd.edu
Journal of the American Chemical Society
|November 17, 2005
概括
复合物与β-二甲基酸连接体表现出电子不对称性,使其能够进行性识别. 这种电子效应,而不是硬质阻碍,驱动了-BINOL复合体中的 diastereoselectivity.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 立体化学是一种立体化学.
背景情况:
- 在C2对称的复合体中的β-二甲基酸连接体会产生电子不对称性.
- 最低无人分子轨道 (LUMO) 是一个倾斜的 dz2 轨道,受到的配置的影响.
研究的目的:
- 为了研究电子不对称性在合识别中的作用.
- 为了探测-BINOL复合物的二选择性.
主要方法:
- 用1.1'-bi-2-naphtholate (BINOL) 合成的-β-二甲酸复合物.
- 核磁共振 (NMR) 光谱法用于确定二聚体比率.
- 相关复合物的结晶学,以建立立体化学.
主要成果:
- -BINOL复合物只形成一个二聚体,正如电子因子所预测的那样.
- 结晶学证实了基于电子基础的预测立体化学.
- 锡类同类显示出明显较低的二元体选择性,支持电子控制.
结论:
- 复合体中的电子不对称性对于性识别至关重要.
- 观察到的二元体选择性主要是由电子效应决定的,而不是硬体因素.
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