DOI: 10.1016/j.molstruc.2012.04.049

The tautomerism of fluorinated indazolinones in the solid state

The structure of three fluorinated NH-indazolinones, two oxo derivatives and one 3-hydroxyindazole, has been determined by ¹³C and ¹⁵N solid state NMR. For two of them, X-ray crystallography confirmed the results on the tautomeric forms, 4,5,6,7-tetrafluoroindazolin-3-one crystallizing in P2₁/c monoclinic space group and 6,7-difluoroindazolin-3-one in P2₁/n monoclinic space group, proving once more the efficiency of the combined use of both techniques in structural determination. DFT theoretical calculations, gas phase, water-PCM and one explicit water molecule, support the results.