电子对原子道的作用:单质代替代酸衍生物的构造性异构化
Shadi Amiri1, Hans Peter Reisenauer, Peter R Schreiner
1Institute for Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany.
Journal of the American Chemical Society
|October 23, 2010
概括
我们使用乳标签识别了酸的不稳定E形变体,通过道化观察其快速转化为Z形. 量化了道工艺上的替代效应,建立了原子道的第一个哈梅特关系.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 量子化学 是一个量子化学.
背景情况:
- 酸是最简单的芳香性碳酸,由于快速的H道化,它主要存在于Z调形体中.
- 较高的E调整器是短暂的,很难直接观察.
研究的目的:
- 使用矩阵隔离技术,通过光谱学识别佐酸的E调整体.
- 研究D道化在酸衍生物中的动力学和替代效应.
- 为了建立原子道的第一个哈梅特关系.
主要方法:
- 矩阵隔离光谱在11K的Ar.
- 酸的O-化形成 (E) -d(1)-1a.a. 的形式.
- 量子化学计算 (CCSD(T) /cc-pVTZ//MP2/cc-pVDZ + ZPVE) 用于道路径分析.
- 对准替代的酸衍生物的系统研究.
主要成果:
- 产生和识别了酸的O-低化E调节器 (E) -d(1)-1a.
- (E) -d(1)-1a表现出快速的D道化到Z符合性,其半衰期在11K的Ar中为12分钟.
- 由于更快的H道化,计算研究预测父 (E) -1a的半衰期要短得多 (~10^-5分钟),这是由于更快的H道化.
- 量化了电子替代效应,表明电子捐赠者增加了道化半衰期,而接受者减少了它.
- 第一个实验和计算的哈梅特关系 (σ(t)) 对于原子道的得出.
结论:
- 酸的E调整器可以通过带有同位素标记的矩阵隔离获得,但通过D道快速异构成Z形式.
- 道的速度受到电子替代效应的显著影响,正如哈梅特关系所描述的那样.
- 这项工作为有机分子中的量子道现象提供了基本的见解,并建立了量化道上的替代效应的新方法.
相关概念视频
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