N′-(2,4-Dinitrophenyl)acetohydrazide monohydrate

In the crystal structure of the title compound, C8H8N4O5·H2O, the organic and lattice water molecules are linked together via N—H⋯O and O—H⋯O hydrogen bonds. A C—H⋯O interaction is also observed between the organic molecules. These hydrogen bonds and interactions lead to the formation of a three-dimensional network. An intramolecular N—H⋯O hydrogen bond also occurs. The dihedral angle between the acetyl group and the almost planar hydrazide moiety [maximum deviation from the least-squares plane is 0.209 (2) Å for one of the nitro O atoms] is 88.5 (3)°.

In the crystal structure of the title compound, C 8 H 8 N 4 O 5 ÁH 2 O, the organic and lattice water molecules are linked together via N-HÁ Á ÁO and O-HÁ Á ÁO hydrogen bonds. A C-HÁ Á ÁO interaction is also observed between the organic molecules. These hydrogen bonds and interactions lead to the formation of a three-dimensional network. An intramolecular N-HÁ Á ÁO hydrogen bond also occurs. The dihedral angle between the acetyl group and the almost planar hydrazide moiety [maximum deviation from the least-squares plane is 0.209 (2) Å for one of the nitro O atoms] is 88.5 (3) .
The bond distances and angles in the title compound ( Fig. 1) agree very well with the corresponding bond distances and angles reported in a closely related compound (Okabe, et al., 1993). There is a strong intramolecular N-H···O hydrogen bond that stabilizes the molecular structure of the title compound. In the crystal structure, pairs of symmetry-related molecules are connected into centrosymmetric clusters via medium O-H···O and N-H···O hydrogen bonds forming twenty-six-membered rings with an R 6 6 (26) motif (Bernstein, et al., 1995). The water molecule is surrounded by three organic groups through hydrogen bonds type O-H···O and N-H···O. The crystal packing (Fig. 2) is stabilized by these intermolecular hydrogen bonds and C-H···O interactions (Table 1) resulting in a three dimensional network.
The obtained solution was stirred at 333 K for 30 min and then left to stand at room temperature. Yellow single crystals of the title compound were obtained after some days.

Refinement
H atoms were treated as riding, with C-H = 0.93 and 0.96 A° for phenyl and methyl H-atoms, respectively. The H-atoms bonded to O and N were located from difference maps and were allowed to refine freely. The U iso (H) were allowed at 1.5U eq (C methyl) or 1.2U eq (C phenyl).

Figure 2
Unit cell packing of the title compound projected along the a axis. The H-atoms not involved in H-bonding are omitted. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq OW 0.8341 (