UV/Vis, IR and 1H NMR spectrophotometric studies of some bisazo-dianil compounds based on bis-(hydroxy, formyl) phenylazo phenylene and anthranilic acid.
The electronic absorption spectra of some bisazo-dianils are studied in organic solvents of different polarity and in buffer solutions of varied pH. The different absorption bands are assigned to the corresponding electronic transitions, the solvent effect on the CT band energy is also discussed. The spectral study in buffer solutions is utilized for the determination of the pKa of the phenolic OH-groups. The important bands in the IR spectra as well as the signals of the 1H NMR spectra are assigned and discussed in relation to molecular structure. The fluorescence spectra of the compounds are recorded. The fluorescence quantum yield and pK in the ground and excited states are determined.
Issa
Raafat M
RM
Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt.
El-Baradie
Kamal Y
KY
El-Wakiel
Nadia A
NA
D001391:Azo Compounds / Q000737:chemistry*; D002021:Buffers; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D012997:Solvents; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
D001391:Azo Compounds; D002021:Buffers; D012997:Solvents