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单一-三重能量差距的2-纳菲尔 ((carbomethoxy) 碳的溶剂依赖性
Yuhong Wang1, Christopher M Hadad, John P Toscano
1Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Journal of the American Chemical Society
|February 21, 2002
概括
2 - 纳菲尔 ((carbomethoxy) 碳的基本状态从非极性六中的三元变化到极性乙二中的单元变化,由碳的溶剂稳定驱动.
科学领域:
- 物理化学 物理化学
- 有机化学 有机化学
- 计算化学的计算化学
背景情况:
- 碳是具有单元和三元基态的反应性中间体.
- 单元和三元状态之间的能量差异影响了碳烯的反应性.
- 溶剂的极性会影响分子的电子特性和稳定性.
研究的目的:
- 为了研究2-纳 () 基二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二
- 了解溶剂极性如何影响这种碳素的基本状态.
- 量化单元-三元能量差异的和贡献.
主要方法:
- 时间分辨率红外光谱 (TRIR) 被用来探测碳化合物的状态.
- 运用了计算方法,特别是用极化连续解法模型 (PCM) 进行的B3LYP计算.
- 进行了可变温度TRIR实验,以测量热力学参数.
主要成果:
- 2 - 纳 () 基态的2-纳 () 基态转换从中的三元体到酸中的单元体.
- 极性溶剂优先稳定单体碳基,因为它具有较大的二极 Moment.
- 计算质量地重现了实验观察到的体差异.
结论:
- 溶剂极性显著影响单元-三元能量差距和2-纳基基基基基的基本状态.
- 由溶剂和几何学影响的和因素都对观察到的状态偏好有所贡献.
- 计算建模为了解溶剂对碳烯电子结构的影响提供了有价值的工具.
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