Systematic investigations of the kinetics of the reactions of ethyl bromoacetate (EBA) and of picryl bromide (PB) with 2-phenylthiazolidines (PT) in 100% ethanol were undertaken at 30, 35, 40, and 45 °C. The most incisive information concerning the Hammett equation comes from the extensive studies on the substituted 2-phenylthiazolidines, establishing linear Hammett plots with negative ρ values. The kinetic data, plotted in a Brønsted fashion against pKa of the corresponding thiazolidinium ions, yield linear relationships. The activation parameters were computed. The linear relationships between ΔH≠ and ΔS≠ signify a consistent mechanism throughout the series.
在100%乙醇中,对乙基溴乙酸酯(EBA)和硝基溴苯(PB)与2-苯基噻唑啉(PT)的反应动力学进行了系统研究,温度分别为30、35、40和45°C。对取代2-苯基噻唑啉的广泛研究提供了关于Hammett方程最具洞察力的信息,建立了具有负ρ值的线性Hammett图。以对应噻唑啉阳离子的pKa为横坐标,以Brønsted方式绘制的动力学数据呈线性关系。计算了活化参数。ΔH≠与ΔS≠之间的线性关系表明整个系列中存在一致的机理。