关于迈森海默复合中的二甲基硫烯离子的密度
Erwin Buncel1, Kuk-Tae Park, Julian M Dust
1Department of Chemistry, Queen's University, Kingston, Ontario, Canada K7L 3N6. buncele@chem.queensu.ca
Journal of the American Chemical Society
|May 2, 2003
概括
双甲基硫基 (dimsyl) 对1,3,5-三丁 (TNB) 具有独特的O,S和C核友反应性. 确定了三种新的引证,揭示了对dimsyl的独特动力学和热力学偏好.
科学领域:
- 有机化学 有机化学
- 核友反应性 核友反应性
- 频谱学是一种光谱学方法.
背景情况:
- 碳离子的反应性在有机合成中至关重要.
- 双甲基硫基 (dimsyl) 以其核友特性而闻名.
- 1,3,5-三丁 (TNB) 是研究核友芳香替代的常见基质.
研究的目的:
- 为了研究dimsyl.的牙性 (O-,S-,和C-核友反应性).
- 描述dimsyl和TNB之间形成的附加物.
- 为了比较dimsyl与其他核友的反应模式.
主要方法:
- 核磁共振 (NMR) 光谱学被用来研究反应.
- 添加物的结构是根据光谱数据分配的.
- 分析了动力学和热力学偏好.
主要成果:
- 首次观察到三种具有TNB的新型dimisyl附加物:O-附加物15,S-附加物16和C-附加物17.
- 发现,对 adduct 形成的动力偏好是 15 > 16 > 17.
- 热力学偏好被确定为17 > 16 > 15.
结论:
- 迪姆西尔表现出独特的三核性特性,通过氧,硫和碳反应.
- 观察到的dimisyl的反应模式与酸和二甲基硫氧化物的反应模式不同.
- 迪姆西尔代表了一个独特的系统,其中三个相邻的原子可以参与共价键的形成.
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