在铜催化原子转移激素聚合 (Cu-ATRP) 中对联体和启动效应的机械指导预测模型
Cheng Fang1,2, Marco Fantin3, Xiangcheng Pan3
1Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States.
Journal of the American Chemical Society
|April 13, 2019
概括
这项研究通过计算分析了铜催化原子转移基聚合 (Cu-ATRP) 的过渡状态. 它揭示了催化剂的电子性质,配体的性和骨干的灵活性决定了激活/失活率,从而实现了反应性的预测模型.
科学领域:
- 聚合物化学
- 计算化学
- 催化剂
背景情况:
- 铜催化转移基聚合 (Cu-ATRP) 是一种广泛使用的受控聚合技术.
- 有机学研究,但激活/禁用平衡的过渡状态仍然未经计算研究.
- 对Cu-ATRP速率的影响的理解是有限的.
研究的目的:
- 执行Cu-ATRP激活过渡状态的第一个计算分析.
- 阐明影响激活和关闭速率的因素.
- 开发Cu-ATRP反应性的预测模型.
主要方法:
- 对Cu-ATRP激活过渡状态的计算分析.
- 研究Br原子转移几何和相互作用.
- 识别电子,硬体和灵活性描述符.
- 多变量线性回归将描述符与实验数据相关联.
主要成果:
- Br原子转移通过异常的曲几何与聚合物链末端连接发生.
- 激活/失活速率取决于催化剂的电子性质和联体启动器的硬体排斥.
- 结合体脊柱的灵活性对激活有重大影响.
- 确定了HOMO能量,埋藏体积的百分比和扭曲能量作为关键描述.
- 开发了具有高准确度的联体和启动效应预测模型 (平均误差<2kcal/mol).
结论:
- 这项研究为Cu-ATRP过渡状态提供了第一个计算洞察力.
- 已建立的描述器和预测模型提供了理解和调整Cu-ATRP反应性的强有力的方法.
- 这些发现有助于对Cu-ATRP的机理理解和实际应用.
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