Department of Chemistry and Biochemistry, University of Oklahoma , Norman, Oklahoma 73019, United States.
J Phys Chem B. 2013 Nov 21;117(46):14432-7. doi: 10.1021/jp4079019. Epub 2013 Nov 8.
The dependence of the reaction rate on solvent dielectric constant is examined for the reaction of trihexylamine with 1-bromohexane in a series of 2-ketones over the temperature range 25-80 °C. The rate constant data are analyzed using the compensated Arrhenius formalism (CAF), where the rate constant assumes an Arrhenius-like equation that also contains a dielectric constant dependence in the exponential prefactor. The CAF activation energies are substantially higher than those obtained using the simple Arrhenius equation. A master curve of the data is observed by plotting the prefactors against the solvent dielectric constant. The master curve shows that the reaction rate has a weak dependence on dielectric constant for values approximately less than 10 and increases more rapidly for dielectric constant values greater than 10.
考察了三正己胺与 1-溴己烷在一系列 2-酮中的反应速率对溶剂介电常数的依赖性，温度范围为 25-80°C。使用补偿 Arrhenius 形式主义 (CAF) 分析速率常数数据，其中速率常数采用类似于 Arrhenius 的方程，该方程还在指数前因子中包含介电常数依赖性。CAF 活化能明显高于使用简单 Arrhenius 方程获得的值。通过将前因子绘制为溶剂介电常数，可以观察到数据的主曲线。主曲线表明，对于介电常数约小于 10 的值，反应速率对介电常数的依赖性较弱，而对于介电常数大于 10 的值，反应速率的依赖性增加得更快。
