多元曲线分辨结合在线红外光谱用于4-氨基-3,5二甲基吡唑的合成机理研究

Study on synthesizing mechanism of 4-amino-3,5-dimethyl pyrazole by using multivariate curve resolution combined with online infrared spectroscopy

应用红外光谱在线监测2,3,4-戊三酮-3-肟和水合肼合成4-氨基-3,5-二甲基吡唑的反应过程,采用多元曲线分辨-交替最小二乘法(MCR-ALS)以及直观推导式演进特征投影法(HELP)等化学计量学方法对所获得的实时动力学红外光谱数据矩阵进行解析,获得了反应物、中间体及产物的浓度变化曲线和对应的红外光谱。并将两种方法的分析结果进行比较,得出可相互验证的一致结论,以此推出该反应的合理机理。结果表明实验所选的化学计量学方法结合在线红外可以快速、有效反映4-氨基-3,5-二甲基吡唑合成过程中各组分的浓度变化和红外光谱的变化,对其反应机理的研究具有重要的指导意义。

Application of on-line infrared spectroscopy to monitor the reaction process of synthesizing 4-amino-3,5-dimethyl pyrazole from 2,3,4-pentatrione-3-oxime and hydrazine hydrate. The concentration profiles and spectra of the reactant, intermediates and product were obtained by analyzing the real-time dynamics of the infrared spectral data and using chemometric methods such as multiple curve resolution-alternating least squares （MCR-ALS）, heuristic evolving latent projections （HELP） and etc. The reasonable mechanism was induced by the same conclusion acquired from comparing MCR-ALS with HELE The experimental results showed that the selected chemometric methods combined with on-line infrared could reflect quickly each component concentration and infrared spectra about the synthesis process of 4-amino-3,5-dimethyl pyrazole. It should provide significant guidance to the investigation of the reaction mechanism.