Tautomerism of 1-(2′,4′-dinitrophenyl)-3-methyl-2-pyrazolin-5-one: theoretical calculations, solid and solution NMR studies and X-ray crystallography

@article{Dardonville1998TautomerismO1,
  title={Tautomerism of 1-(2′,4′-dinitrophenyl)-3-methyl-2-pyrazolin-5-one: theoretical calculations, solid and solution NMR studies and X-ray crystallography},
  author={Christophe Dardonville and Jos{\'e} Elguero and Isabel Rozas and Cristina Fern{\'a}ndez-casta{\~n}o and Concepci{\'o}n Foces-Foces and Isabel Sobrados},
  journal={New Journal of Chemistry},
  year={1998},
  volume={22},
  pages={1421-1430}
}
To gain a better understanding of the tautomerism of 1-(2′,4′-dinitrophenyl)-3-methyl-2-pyrazolin-5-one, 2, different studies were performed. In order to simulate the gas phase, several MO calculations at the semiempirical (AM1 and PM3) and abinitio (HF/6-31G* and B3LYP/6-31G*) levels were carried out on the different tautomers of this compound and on those of the corresponding 1-phenyl derivative 4. The 1H and 13C NMR spectra were recorded in solution for compound 2. Finally, to investigate… Expand
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