能量溶解的碰撞诱导解离截面的2:1 bis-oxazoline铜复合体. 非结合性相互作用和非线性效应
Eva Zocher1, Rolf Dietiker, Peter Chen
1Laboratorium für Organische Chemie, ETH Zürich, Switzerland.
Journal of the American Chemical Society
|February 10, 2007
概括
这项研究确定了铜复合体的连接体结合能. 奇拉复合体之间的稳定性差异预测了不对称催化中的非线性效应,由连接体替代剂驱动.
科学领域:
- 协调化学 协调化学
- 催化剂是一种催化剂.
- 物理化学 物理化学
背景情况:
- 与铜 (I) 复合的 bis-oxazoline 配体在不对称催化过程中至关重要.
- 催化中的非线性效应源于同体和异体复合物的不同稳定性.
- 了解这些稳定性差异是优化催化反应的关键.
研究的目的:
- 为了确定2:1 bis-oxazoline/Cu(I) 复合物的绝对连接体结合能.
- 为了研究连接物替代剂 (异基与基) 如何影响复合体稳定性.
- 为了将复杂稳定性与在不对称催化中预测非线性效应的相关性.
主要方法:
- 使用能量解析的碰撞诱导解离 (CID) 截面测量.
- 在质谱分析中使用伪反体配体.
- 装配CID数据以确定气相中的绝对结合能.
主要成果:
- 固态上相似但电子上不同的异和替代物诱导了同型和异体复合物的不同稳定性顺序.
- 异基替代联体由于其稳定性顺序,在不对称催化中预测非线性效应.
- 基之间的非共价相互作用显著影响稳定性,但DFT计算并没有很好地捕捉到它们.
结论:
- 连接体替代物标识极大地影响了性铜复合体的相对稳定性.
- 这种稳定性差异直接预测了不对称催化剂中非线性效应的发生和大小.
- 对非共价相互作用的准确建模对于预测催化结果至关重要.
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