在乙和二甲基硫氧化物中类酸盐复合物的粘合异质解能上的溶剂作用
Bin-Rui Mo1, Jin-Dong Yang1,2, Jin-Pei Cheng1,3,2
1Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China.
The journal of physical chemistry letters
|April 10, 2025
概括
研究了溶剂极性对-氧键的影响. 令人惊的是,低极性乙二比高极性二甲基硫氧化物更能稳定离子物种,从而逆转了预期的热力学.
科学领域:
- 有机金属化学 有机金属化学
- 物理化学 物理化学
- 计算化学计算化学
背景情况:
- 溶剂通过溶解反应物和中间体,显著影响化学反应.
- 了解溶剂效应对于控制反应途径和结果至关重要.
- -氧键异解是各种催化过程中的关键步骤.
研究的目的:
- 为了研究溶剂极性的影响Ni-O键异解能量 (ΔGhet(Ni-O)) 在类酸盐.
- 为了比较二甲基硫氧化物 (DMSO) 和乙二 (MeCN) 的稳定能力,用于Ni-O键裂解过程中形成的离子物种.
- 阐明观察到的溶剂效应背后的潜在机制,特别是低极性溶剂的反直觉稳定.
主要方法:
- 在DMSO和MeCN中实验性确定烯酸酸盐的Ni-O键异解能 (ΔGhet(Ni-O)) .
- 使用光谱和电化学技术来探测反应中间体和热力学.
- 使用理论计算 (例如,DFT) 来建模溶剂-溶解物相互作用,并了解电子效应.
主要成果:
- 发现DMSO中的Ni-O键异质化能量 (ΔGhet(Ni-O)) 比MeCN中更大.
- 低极性溶剂氨 (MeCN) 与高极性溶剂二甲基硫氧化物 (DMSO) 相比,对离子物种的稳定性更强.
- 这种稳定效应被发现是系统的特征,而不是在类似的系统中观察到的.
结论:
- 该研究挑战了对溶剂极性影响的传统理解,证明低极性溶剂可以有效地稳定离子中间体.
- 溶剂选择极大地影响了Ni-O键异解的热力学,对催化剂设计和反应优化有影响.
- 系统中独特的溶剂效应突出显示了金属-连接体相互作用和溶解之间的复杂相互作用,与其他过渡金属 (如) 截然不同.
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