DMAP催化2-(噻吩-2-基)乙基对甲苯磺酸酯反应机理及动力学研究

Study on the reaction mechanism and kinetics of DMAP catalyzed reaction of 2-(2-Thienyl)ethyl toluene-p-sulphonate

目的:探究4-二甲氨基吡啶(DMAP)催化2-(噻吩-2-基)乙基对甲苯磺酸酯的机理和动力学。方法:利用在线傅里叶变换红外光谱(FTIR)对反应过程进行监测,采用多元曲线分辨和二维相关光谱(2DCOS)技术分析反应路径,并通过红外定量方法建立了反应动力学模型。结果:当DMAP参与反应时,会催化对甲苯磺酰氯和2-噻吩乙醇先生成中间体(IM)然后脱氢生成产物。确定了1644 cm^(-1)附近的波数为中间体的特征吸收峰,计算两个限速步骤的动力学参数,两步活化能分别为29.75 kJ/mol和40.04 kJ/mol。结论:这种对FTIR数据的分析方法可以从复杂的实时数据中提取反应路径组分的有用信息。

Aims:This paper aims to investigate the mechanism and kinetics of DMAP catalyzed reaction of 2-(2-Thienyl)ethyl toluene-p-sulphonate catalyzed with DMAP.Methods:The reaction process was monitored by the online Fourier transform infrared spectroscopy(FTIR).The reaction path was analyzed by multiple curve resolution and two-dimensional correlation spectroscopy(2 DCOS);and the reaction kinetic model was established with the infrared quantitative method.Results:When DMAP was involved in the reaction,it would catalyze the formation of an intermediate(IM)between p-toluene sulfonyl chloride and 2-thiophene ethanol and then dehydrogenate to form the product.The wave number near 1644 cm^(-1)was determined as the characteristic absorption peak of the intermediate;and the kinetic parameters of the two rate-limiting steps were calculated.The activation energies were 29.75 kJ/mol and 40.04 kJ/mol,respectively.Conclusions:This method of FTIR analysis can extract useful information about reaction components from complex real-time data.