狄米西基O氧化物:光谱特征,形状和反应模式:OH形成和OH捕获
1Lehrstuhl für Organische Chemie II der Ruhr-Universität, D-44780 Bochum, Germany.
Journal of the American Chemical Society
|July 18, 2001
概括
用NMR光谱和DFT计算合成了二甲基氧化物Dimesitylketone O-oxide,一种碳氧化物,并通过NMR光谱和DFT计算确认了其结构. 这项研究证明了碳氧化物在溶液中产生基基的潜力.
科学领域:
- 有机化学 有机化学
- 摄影化学的使用.
- 计算化学计算化学
背景情况:
- 碳氧化物是反应性中间体,在大气化学和有机合成中起着重要作用.
- 了解它们的结构,稳定性和反应途径对于预测化学转变至关重要.
研究的目的:
- 为了合成和表征dimesitylketone O-oxide (1b) 的作用.
- 用实验和计算方法阐明1b的首选形状和几何.
- 研究1b.的热衰变路径和激活障碍.
主要方法:
- 在140 K的氧和CCl3F中对二极二甲进行光解.
- 核磁共振 (NMR) 谱学用于结构确定.
- 密度函数理论 (DFT) 计算,包括IGLO和B3LYP/cc-pVTZ水平,用于几何优化和激活度计算.
主要成果:
- Dimesitylketone O-oxide (1b) 已经成功地合成出来.
- 实验性NMR化学转移与DFT计算的值密切匹配,证实了与COO平面垂直的梅西环的分子几何.
- 首选的反应途径涉及从一个正甲基组的H迁移,计算的激活度为12.7kcal/mol.
- 热衰变激活障碍在CCl3F中被确定为13.8 ± 0.2 kcal/mol,在乙二中为13.1 ± 0.4 kcal/mol.
- 迁移导致OO键裂变,形成OH和基,随后的重组或逃逸会影响产品的形成.
结论:
- 这项研究证实了dimesitylketone O-oxide的结构和首选反应途径.
- 这些发现支持在溶液相反应中从碳氧化物产生基 (OH) 的可能性.
- 这对了解各种化学环境中的氧化机制具有重要意义.
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