The solubilities of phenylboronic acid, its pinacol ester and azaester in organic solvents (chloroform, 3-pentanone, acetone, dipropyl ether and methylcyclohexane) have been determined experimentally by a dynamic method, in which the disappearance of turbidity was determined by measuring of light intensity using a luminance probe. Phenylboronic acid has high solubility in ether and ketones, moderate in chloroform and very low in hydrocarbon. Pinacol ester and azaester show better solubility than the parent acid in all tested solvents. For pinacol ester differences between particular solvents are small, while for azaester the differences are significant. For both esters the highest solubility is observed in chloroform and the lowest in the hydrocarbon. The results have been correlated by the Wilson, NRTL and Redlich–Kister equations. For the phenylboronic acid better correlation of the data is obtained by polynomials in comparison with the above equations. It is connected with additional acid-anhydride equilibrium in the system. The influence of polarity of the solvents on the solubility is discussed.

中文翻译：

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苯硼酸及其环酯在有机溶剂中的溶解度

苯基硼酸及其频哪醇酯和氮杂酯在有机溶剂（氯仿、3-戊酮、丙酮、二丙醚和甲基环己烷）中的溶解度已通过动态方法进行实验测定，其中浊度的消失是通过测量光强度来确定的。使用亮度探针。苯硼酸在醚类和酮类中溶解度高，在氯仿中溶解度适中，在烃类中溶解度极低。频哪醇酯和氮杂酯在所有测试溶剂中显示出比母体酸更好的溶解度。对于频哪醇酯，特定溶剂之间的差异很小，而对于氮杂酯，差异很大。对于这两种酯，在氯仿中的溶解度最高，在烃中的溶解度最低。结果已通过 Wilson、NRTL 和 Redlich-Kister 方程相关联。对于苯基硼酸，与上述方程相比，通过多项式获得更好的数据相关性。它与系统中额外的酸酐平衡有关。讨论了溶剂极性对溶解度的影响。