评论"化学反应期间的分子运动:没有积极推进的证据"和"点击反应组件的分子扩散性:扩散增强问题"
Tian Huang1, Steve Granick1,2
1Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan 44919, South Korea.
Journal of the American Chemical Society
|August 3, 2022
概括
这项研究驳斥了在铜催化酸循环添加 (CuAAC) 反应中缺少增强扩散的说法. 即使使用MRI对比剂并纠正有缺陷的实验比较,
科学领域:
- 化学学
- 化学动力学
- 物理化学
背景情况:
- 铜催化亚酸循环添加 (CuAAC) 反应是化学反应的基石.
- 通过化学
- 已知具有独特的运动性质.
- 最近的研究提出了关于这种反应中的扩散率的相互矛盾的结果.
- 具体来说,报告已经讨论了"扩散"的存在或不存在.
研究的目的:
- 批判性地评估和反驳两篇最近的JACS文章, 质疑我们的实验室在CuAAC反应中扩散的发现.
- 解决先前研究中使用的扩散NMR实验的方法缺陷.
- 在CuAAC反应中恢复扩散的有效性.
主要方法:
- 重新分析扩散NMR实验,特别是针对加多 (Gd3+) 酸盐的影响.
- 在扩散测量中对实验参数进行校正,以考虑MRI对比剂的特性.
- 在比较扩散研究中对参考状态的选择进行批评.
主要成果:
- 我们证明在扩散NMR实验中使用Gd3+-chelate,由于其固有的特性,Fillbrook等在概念上有缺陷.
- 尽管存在Gd3+-酸盐,但通过调整实验技术,我们证实了CuAAC反应中扩散的存在.
- 我们确定并批评Rezaei-Ghaleh等人使用的非物理参考状态. 为了比较.
结论:
- 在CuAAC反应中增强扩散的发现是稳固的和可重复的.
- 方法上的错误,特别是关于Gd3+-酸盐的使用和不合适的参考状态,导致了先前研究的错误结论.
- 这项研究再次证实了促进扩散对于了解CuAAC反应的动力学的重要性.
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