吡啶二甲酸结构异构体的太赫兹光谱分析  

Terahertz Spectroscopy of the Structural Isomers of Pyridine Dicarboxylic Acid

作　　者：骆国防 齐济 刘雅丽 何明霞[2] 黄华 曲秋红[2] 张逸竹 LUO Guo-fang;QI Ji;LIU Ya-li;HE Ming-xia;HUANG Hua;QU Qiu-hong;ZHANG Yi-zhu(State Grid Shanghai Electric Power Research Institute,Shanghai 200437,China;School of Precision Instrument and Optoelectronic Engineering,Tianjin University,Tianjin 300072,China;State Grid Shanghai Electric Power Company,Shanghai 200437,China)

机构地区：[1]国网上海市电力公司电力科学研究院,上海200437 [2]天津大学精密仪器与光电子工程学院,天津300072 [3]国网上海市电力公司,上海200437

出　　处：《光谱学与光谱分析》2025年第4期908-913,共6页Spectroscopy and Spectral Analysis

基　　金：国家电网有限公司科技项目资助(52094024001K);国家自然科学基金面上项目(12174284)资助。

摘　　要：在食品和药品生产过程中,同分异构体的识别和区分是一个重要且复杂的问题,尤其是在它们分子式相同但晶体结构不同的情况下。吡啶二甲酸作为一种广泛应用于医药合成的关键中间体,不同的异构体表现出不同的物理和化学性质,对其进行有效区分尤为关键。太赫兹光谱技术被视作检测同分异构体的新手段,利用高分辨率太赫兹时域光谱仪对2,3-吡啶二甲酸、2,4-吡啶二甲酸、2,5-吡啶二甲酸、3,4-吡啶二甲酸以及3,5-吡啶二甲酸进行测量,揭示了它们在不同质量分数下的独特太赫兹吸收特征。这些异构体的吸收特性在太赫兹波段有不同差异。通过密度泛函理论计算,对比了理论模拟与实验测量结果,揭示了这些化合物的主要振动模式,包括羧基和吡啶环的扭转振动、键角弯曲以及它们的耦合作用。研究展现了太赫兹光谱在物质鉴别方面的独特优势,并指出其与红外光谱的显著区别。研究结果不仅为理解吡啶二甲酸衍生物的太赫兹光谱特征提供了参考,也展示了太赫兹光谱在化学物质分析和识别方面的应用潜力,对医药中间体的合成和鉴别提供了新的依据。In the production processes of food and pharmaceuticals,the identification and differentiation of stereoisomers constitute a crucial and complex issue,particularly when their molecular formulas are identical,but their crystal structures differ.Pyridine dicarboxylic acids serve as key intermediates widely used in pharmaceutical synthesis,where effective discrimination between different isomers is essential due to their varied physical and chemical properties.The technique of terahertz spectroscopy has emerged as a novel approach for detecting stereoisomers,employing high-resolution terahertz time-domain spectrometers to measure 2,3-pyridine dicarboxylic acid,2,4-pyridine dicarboxylic acid,2,5-pyridine dicarboxylic acid,3,4-pyridine dicarboxylic acid,and 3,5-pyridine dicarboxylic acid,revealing their unique terahertz absorption features at different mass fractions.These isomers exhibit distinct absorption characteristics in the terahertz range.Through density functional theory calculations,a comparison between theoretical simulations and experimental measurements has been conducted,elucidating the primary vibrational modes of these compounds,encompassing the torsional vibrations of carboxyl groups and pyridine rings,bond angle bending,and their coupling effects.The research has demonstrated the unique advantages of terahertz spectroscopy in material identification,highlighting its significant differences from infrared spectroscopy.The findings not only offer insights into the terahertz spectral features of pyridine dicarboxylic acid derivatives but also showcase the potential applications of terahertz spectroscopy in the analysis and identification of chemical substances,providing new foundations for the synthesis and discrimination of pharmaceutical intermediates.

关 键 词：太赫兹时域光谱 吡啶二甲酸 密度泛函理论 同分异构体 

分 类 号：O433[机械工程—光学工程]