title: UV-vis, IR and 1H NMR spectroscopic studies of some mono- and bis-azo-compounds based on 2,7-dihydroxynaphthalene and aniline derivatives.
abstract: The absorption spectra of mono- and bis-azo-derivatives obtained by coupling the diazonium salts of aromatic amines and 2,7-dihydroxynaphthalene have been studied in six organic solvents. The different absorption bands have been assigned and the effect of solvents on the charge transfer band is also discussed. The diagnostic IR spectral bands and 1H NMR signals are assigned and discussed in relation to molecular structure. Also, semi-empirical molecular orbital calculations using the atom superposition and electron delocalization molecular orbital (ASED-MO) theory have been performed to investigate the molecular and electronic structures of these compounds. According to these calculations, an intramolecular hydrogen bonding is essential for stabilization of such molecules.
authors.affiliation: Chemistry Department, Faculty of Science, Tanta University, 31527 Tanta, Egypt.
authors.forename: Raafat M
authors.initials: RM
authors.lastname: Issa
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Fayed
authors.forename: Mohammed K
authors.initials: MK
authors.lastname: Awad
authors.forename: Sanaa M
authors.initials: SM
authors.lastname: El-Kony
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D001391:Azo Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D015394:Molecular Structure; D009284:Naphthols / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000814:Aniline Compounds; D001391:Azo Compounds; D009284:Naphthols; C107946:2,7-dihydroxynaphthalene; C023650:aniline