摘要
ＡｓｓｉｇｎａｔｉｏｎｏｆＡｃｉｄｉｃＤｉｓｓｏｃｉａｔｉｏｎＣｏｎｓｔａｎｔｓｏｆＤｉｍｅｔｈｏｘｙｐｈｅｎｙｌｆｌｕｏｒｏｎｅａｎｄＤｉｂｒｏｍｏｄｉｍｅｔｈｙｌａｍｉｎｏｐｈｅｎｙｌｆｌｕｏｒｏｎｅＣｈｅｎＴｉａｎ－Ｍｉｎｇ；ＷａｎｇＤｏｎｇ－...
The acidic dissociation constants of dimethoxyhenylfluorone (DMOPF)and dibromo-dimethylaminophenylflurone(Br_2-DMAPF) were determined from a spectrophotometric study, with the results as follows:DMOPF: pk_1=2. 68 pk_2=6. 79 pk_3=9.25 pk_4=12. 14 Br_2-DMAPF: pk_1=2.08 pk_2=4. 12 pk_3=9. 02 pk_45=11.02 The assignation for the possibly occurred shapes in media of various acidity has been accomplished by comparing the calculated results of π-electronic distribution and maximum absorption wave lengths from Huckel molecular orbital(HMO) method with those from the spectrophotometric ones.
