The tautomerism of some substituted 2-hydroxypyridines is investigated by UV/Vis- and 1H-, and 13C-NMR spectroscopic methods, with the aid of the N-Me and O-Me fixed parents. NMR spectroscopic data do not allow discrimination between the two tautomeric forms (with the exception of the unsubstituted 2-hydroxypyridine), while UV/Vis- data permit the quantitative determination, in different solvents, of the amounts of the two forms. The electronic substituent effect and the change of solvent are discussed. An X-Ray diffraction study carried out on a crystal of 2-hydroxy-5-nitropyridine (7) reveals that this compound, in the solid state, is in the oxo-form.
Forlani, L., Cristoni, G., Boga, C., Todesco, P.E., Del Vecchio, E., Selva, S., et al. (2002). Reinvestigation of the tautomerism of some substituted 2-hydroxypyridines. ARKIVOC, 2002(11), 198-215.
Reinvestigation of the tautomerism of some substituted 2-hydroxypyridines
Boga C.;Todesco P. E.;Del Vecchio E.;Monari M.
2002
Abstract
The tautomerism of some substituted 2-hydroxypyridines is investigated by UV/Vis- and 1H-, and 13C-NMR spectroscopic methods, with the aid of the N-Me and O-Me fixed parents. NMR spectroscopic data do not allow discrimination between the two tautomeric forms (with the exception of the unsubstituted 2-hydroxypyridine), while UV/Vis- data permit the quantitative determination, in different solvents, of the amounts of the two forms. The electronic substituent effect and the change of solvent are discussed. An X-Ray diffraction study carried out on a crystal of 2-hydroxy-5-nitropyridine (7) reveals that this compound, in the solid state, is in the oxo-form.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
