可逆的分子间E-H氧化添加到几何变形和结构动态的三化物中
Wei Zhao1, Sean M McCarthy, Ting Yi Lai
1Department of Chemistry and ‡X-ray Crystallography Laboratory, Department of Biochemistry and Molecular Biology, The Pennsylvania State University , University Park, Pennsylvania 16802, United States.
Journal of the American Chemical Society
|November 18, 2014
概括
在几何上受到限制的三坐标化合物在中表现出低能量反转. 这些化合物经过与O-H和N-H化合物的氧化添加,形成可逆五坐标 adducts.
科学领域:
- 有机化学化学 有机化学
- 协调化学 协调化学
- 无机合成 无机合成
背景情况:
- 三坐标 (σ(3) -P) 化合物在化学中是基本的.
- 几何约束可以显著影响化合物的反应性和特性.
- 三三化酸盐为金属中心提供独特的硬质和电子环境.
研究的目的:
- 为了合成和描述新的几何约束三坐标化合物.
- 为了研究中心的反转动力学.
- 探索这些化合物的反应性,特别是它们的氧化添加能力.
主要方法:
- 通过三三胺基酸盐支持的三坐标化合物的合成.
- 可变温度核磁共振 (NMR) 谱学用于研究逆转.
- 密度函数理论 (DFT) 计算以阐明反转机制.
- 用X射线晶体学和多核核核磁共振光谱学来进行 adducts 的结构性特征.
主要成果:
- 一种Cs-对称的三坐标化合物 (2) 被合成并进行结构特征.
- 在溶液中观察到低能量的逆转 (ΔG‡((exptl) ((298) = 10.7(5) kcal/mol).
- DFT计算表明,通过C2对称的中间体,有一个边缘反转机制.
- 化合物2的核友性较差,但很容易与O-H和N-H化合物进行氧化添加.
- 形成了五坐标 adducts,展现了跨越三角形双金字塔和正方形平面几何学的结构.
- 氧化添加被发现是可逆的在高温下挥发性酒精和氨基.
结论:
- 在几何上受到约束的三坐标化合物可以合成具有独特的结构和动态特性.
- 观察到的低能量的反转凸显了酸盐内的中心的灵活性.
- 这些化合物作为氧化添加反应的多功能平台,形成稳定的五坐标添加物,在催化或材料科学中具有潜在的应用.
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