论文部分内容阅读
Solid state ~(13)C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo--deriva-tives were studied and compared with respective results in solutions.Signals of carbon nuclei ofnaphthalene ring were assigned.Tautomeric forms of compounds were determined.It was shownthat 4-(p-NO_2C_6H_4)-azonaphthol-1 and 1-(p-NO_2C_6H_4)-azonaphthol-2 in solid state existed ex-clusively in quinohydrazone form.The other two compounds——1-(C_6F_5)-azonaphthol-2 and 2-(p-CH_3C_6H_4)-azonaphthol-1 in solid state were not found in the form of individual tautomeric mixturesbut in respective tautomeric equilibrium form.Thus,during transition from liquid to solid state,the tautomeric equilibrium was practically unchanged.In solid state it was found that rotation aroundaryl-N bond was hindered in the time scale of NMR spectroscopy.
Solid state ~ (13) C NMR spectra of a series of naphthol-1 and naphthol-2-arylazo-deriva-tives were studied and compared with respective results in solutions.Signals of carbon nuclei of naphthalene ring were were assigned.Tautomeric forms of compounds were determined. It was shownthat 4- (p-NO_2C_6H_4) -azonaphthol-1 and 1- (p-NO_2C_6H_4) -azonaphthol-2 in solid state existed ex-clusively in quinohydrazone form.The other two compounds were 1- (C_6F_5 ) -azonaphthol-2 and 2- (p-CH_3C_6H_4) -azonaphthol-1 in solid state were not found in the form of individual tautomeric mixtures but the corresponding tautomeric equilibrium form.Thus, transition from liquid to solid state, the tautomeric level was practically unchanged. In solid state it was found that rotation aroundaryl-N bond was hindered in the time scale of NMR spectroscopy.