Crystal and molecular structures of pyrazol-3-one derivatives. I. 1,2-Dihydro-5-methyl-2-phenyl-4-(9H-thioxanthen-9-yl)-3H-pyrazol-3-one.

Abstract

The crystal and molecular structure of 1, 2-dihydro-5-methyl-2-phenyl-4- (9H-thioxanthen-9-yl) -3H-pyrazol-3-one was examined by the X-ray diffraction method to establish the predominant tautomeric form (3b) due to the pyrazol-3-one ring in the solid state. The title compound, C23H18N2OS, crystallizes in space group Cc with lattice parameters a=17.675 (8), b=12.421 (3), c=11.374 (7) A, β=132.57 (3)°, and Z=4. In crystals, molecules of 3b are linked by an intermolecular hydrogen bond between the NH and C=O groups.