关于"在化学反应中遵循分子运动: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"的评论
Lucy L Fillbrook1, Jan-Philipp Günther2, Günter Majer2
1School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia.
Journal of the American Chemical Society
|August 3, 2022
概括
本研究涉及铜催化酸循环添加 (CuAAC) 反应中的扩散NMR测量. 研究人员证实没有观察到任何物种的扩散增强,验证了他们最初的发现.
科学领域:
- 化学动力学
- 核磁共振 (NMR) 光谱学
- 超分子化学
背景情况:
- 扩散核磁共振是一种研究分子运动的强大技术.
- 铜催化酸循环添加 (CuAAC) 是化学中广泛使用的"点击"反应.
- 之前的研究报告了CuAAC反应中的扩散增强,促使进一步调查.
研究的目的:
- 回答有关CuAAC反应中扩散NMR测量的意见.
- 澄清任何物种都没有观察到扩散增强.
- 验证以前出版的方法和结论.
主要方法:
- 使用扩散命令NMR光谱 (DOSY) 来监测分子扩散.
- 使用水作为减少剂以消除峰值重叠.
- 研究放松剂,渐变脉冲长度和扩散时间对扩散系数的影响.
主要成果:
- 在CuAAC反应期间没有观察到任何物种的扩散增强.
- 放松剂没有干扰反应动力学或分子扩散.
- 渐变脉冲长度和扩散时间没有影响测量的扩散系数.
- 使用水成功解决了峰值重叠.
结论:
- 观察到的扩散系数是准确和可靠的.
- 稳定状态假设不适用于长时间的扩散测量.
- 这些发现支持了关于CuAAC反应中缺乏扩散增强的最初结论.
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