对氯苯芴酮的合成与离解常数的归属

首次报告了２、６、７三羟基－９－（对氯）苯基荧光酮的合成文法．用分光光度法测出这个试剂共有四级的离解常数：ｐＫ１＝ ２．１４，ｐＫ２＝５．８６，ｐＫ３＝８．７９．ｐＫ４＝ １１．６８．应用休克分子轨道法．对不同酸度下存在的离子形式进行研究．从中性分子的－电荷密度分布大小，对四级离解常数进行归属，同时通过各离子形式的吸收峰波长的计算值与实测的实验值对照，进一步确认离解常数归属的合理性与可靠性．得出四级离解常数所联系的平衡形式。

Assignation of Acidic Dissociation Constants and Synthesis of 2,6,7-Trihydroxyl-9(4''-Chlorophenyl)-3-Fluorone

The synthetic method or 2, 6, 7-trihydroxyl-9-(4'chlorophenyl)-3-fluorone is re- ported. The acidic dissociation constants of this reagent have been determined from spectrophometic data. These results may be summarized as follows: pK1=2.14, pK2= 5.86, pK3= 8.79, pK4=11.68. The ionic shapes of this reagent in media of various acidity have been studied by using Huckel molecular orbital (HMO) method. From distribu- tion of -electron, dissociation constants have been assigned. Comparing the experimental values with the theoretical values of maximum absorptive wave length, we can confirm that assignation of dissociation constants is reasonable.