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在缩的硫酸中进行H NMR光谱的内部标准

Desmond B Ofosu¹, Robert Z Mendoza¹, Paul J Bracher¹

¹Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, MO 63103, USA. paul.bracher@slu.edu.

|June 20, 2025

概括

建议使用二甲基硫和1,4-丁二作为缩硫酸中质子NMR的内部标准. 这些稳定的化合物通过测量脱碳化反应速率常数来验证.

科学领域:

分析化学分析化学
频谱学是一种光谱学.

背景情况:

质子核磁共振 (1H NMR) 光谱是一种强大的分析技术.
使用NMR进行准确的定量分析需要可靠的内部标准,特别是在像缩硫酸这样具有挑战性的矩阵中.
现有的内部标准可能缺乏必要的稳定性或在高度酸性环境中进行交换的耐受性.

研究的目的:

确定和推适合的内部标准,用于1H NMR光谱在缩的硫酸.
评估潜在的内部标准在恶劣的酸性条件下的稳定性和适用性.
在动力学研究中展示选择的内部标准的实际应用.

主要方法:

对八种候选化合物进行选,以检测其热稳定性和对排气和H/D交换的抗性.
使用1H NMR光谱分析缩硫酸中选定的化合物.
监测了一种模型脱碳化反应,以评估内部标准的性能.

主要成果:

硫二甲基和1,4-丁二被确定为最佳的内部标准.
这些化合物表现出优异的热稳定性和耐脱气和H/D交换在缩的硫酸中.
内部标准有助于准确测量模型脱碳化反应的速率常数.

结论:

硫二甲基和1,4-丁二二是高度有效的,并建议在缩硫酸中进行定量1HNMR的内部标准.
经过验证的标准确保在强酸性介质中可靠的光谱分析和运动测量.
这项工作为研究人员在具有挑战性的化学环境中使用NMR提供了至关重要的工具.

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