Crystal structure and packing features of 3-(5-methyl-1 h -pyrazol-3-yl)-2 h -chromen-2-one and 3-(3-methyl-1 h -pyrazol-3-yl)-2 h -chromen-2-one
TL;DR: By means of single crystal X-ray diffraction and DFT calculations, structural features of 3-(5methyl-1H-pyrazol-3-yl)-2H-chromen-2-one and 3-(3-methyl- 1H- pyrazol 3-yl)2H -chromen 2-one obtained by condensing substituted substituted 3-acetoacetyl-2Н-chromEN-2 -ones with semicarbazides are revealed.
Abstract: By means of single crystal X-ray diffraction and DFT calculations the structural features of 3-(5-methyl-1H-pyrazol-3-yl)-2H-chromen-2-one and 3-(3-methyl-1H-pyrazol-3-yl)-2H-chromen-2-one obtained by condensing substituted 3-acetoacetyl-2Н-chromen-2-ones with semicarbazides are revealed. The possibility of the existence of the compound in different tautomeric and rotameric forms in the crystal is shown.
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