Crystal Structure of N-(.ALPHA.-(1-Phenyl-3-methyl-5-pyrazolone-4-ylidene)benzyl)-N'-3,4,5-trimethoxybenzoylhydrazine

Abstract

Pyrazolones are an important group of organic compounds that have also been widely studied. They are interesting for both theoretical and practical reasons. Pyrazolone derivatives play an important role as substructures of numerous pharmaceuticals, agrochemicals, dyes, pigments, as well as chelating agents and extracting agents.1,2 Moreover, they are capable of prototropic tautomerism. 3 Interest in the study of compounds containing hydrazide or hydrazone moieties have increased considerably because of their potentially biological activities, especially as potential inhibitors for many enzymes. In order to further study the relationship between the structure and properties, many derivants have been prepared. 4,5 In this present work, we report on the synthesis and crystal structure of the title compound.A mixture of 1-phenyl-3-methyl-4-benzoylpyrazolone-5 (1 mmol) and 3,4,5-trimethoxybenzoylhydrazide (1 mmol) in anhydrous ethanol (30 ml) was refluxed for 5 h, and then cooled to room temperature. The precipitate was filtered and dried. The crude product was recrystallized from ethanol. Yellow crystals were thus obtained in 49% yield. A single crystal suitable for an X-ray structural analysis was obtained by slowly evaporating from ethanol at room temperature.A yellow crystal having dimensions of 0.20 × 0.17 × 0.16 mm was chosen for X-ray diffraction studies. The measurements were made on a Rigaku-RAXIS-IV diffractometer with graphite-monochromatized Mo Kα radiation (λ = 0.71073 Å) at 291(2)K. The structure was solved by direct methods using SHELXS-97, and refined by full-matrix least squares techniques anisotropically for all non-H atoms. All H atoms were added according to theoretical calculations; H3E and H4E were , Z = 2, R = 0.0605. The inter-or intramolecular N-H·O hydrogen bonds, together with π-π stacking interactions, stabilize the crystal structure by causing the formation of a one-dimensional chain structure.

3-Methyl-1-phenyl-4-[phenyl(8-quinolylamino)methylene]pyrazol-5(4H)-one

“…1), rather than the imine form as in 4-[(Z)-(benzylamino)phenylmethylene]-5-methyl-2-phenyl-2Hpyrazol-3-one (Jiang et al, 2004). Similar tautomerism has also been observed in a pyrazolone-hydrazide compound (Sun et al, 2006). In addition, the present compound also features an intramolecular hydrogen bond between the atoms N3 and O1 ( Fig.…”

4-Hydroxy-3,5-dimethoxybenzaldehyde 3,4,5-trimethoxybenzoylhydrazone monohydrate

“…Molecules containing hydrazone units are of interest to us (Sun et al, 2006) owing to their broad spectrum of activities and applications (Gup & Kirkan, 2005;Ganjali et al, 2006;Getautis et al, 2006). Moreover, many hydrazones have also been used as ligands for complexation of metal ions (Kuriakose et al, 2007).…”

4-Hydroxy-3,5-dimethoxybenzaldehyde isonicotinoylhydrazone monohydrate

“…Moreover, many of hydrazones have also been employed as ligands for complexation of metal ions (Kuriakose et al, 2007). In continuation of our studies on hydrazone derivatives (Sun et al, 2006;, we herein report the synthesis and crystal structure of the title compound, (I).…”

“…Similar structures have also been observed in related hydrazone analogues (Peralta et al, 2007;Raj & Kurup, 2007;Sun et al, 2007). Other reported compounds exist in the enamineketo tautomeric form (Liu et al, 2004;Sun et al, 2006). …”