N′-(4-Hydroxybenzylidene)acetohydrazide monohydrate

In the title compound, C9H10N2O2·H2O, the molecular skeleton of the acetohydrazide molecule is nearly planar [within 0.014 (1) Å]. The molecule adopts a trans configuration with respect to the C=N bond, while the side chain is slightly twisted away from the attached ring, forming a dihedral angle of 9.975 (8)°. The crystal packing exhibits a three-dimensional network composed from alternating acetohydrazide molecules and uncoordinated water molecules, which interact via N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds. A C—H⋯π interaction is also present.

In the title compound, C 9 H 10 N 2 O 2 ÁH 2 O, the molecular skeleton of the acetohydrazide molecule is nearly planar [within 0.014 (1) Å ]. The molecule adopts a trans configuration with respect to the C N bond, while the side chain is slightly twisted away from the attached ring, forming a dihedral angle of 9.975 (8) . The crystal packing exhibits a three-dimensional network composed from alternating acetohydrazide molecules and uncoordinated water molecules, which interact via N-HÁ Á ÁO, O-HÁ Á ÁO and O-HÁ Á ÁN hydrogen bonds. A C-HÁ Á Á interaction is also present.

D-HÁ
Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.  (Ciemerman et al., 1997). They are also important ligands, which have been reported to have mild bacteriostatic activity and potential oral iron-chelating drugs for genetic disorders such as thalassemia (Offe et al., 1952, Richardson et al., 1988. Metal complexes based on Schiff bases have received considerable attention because they can be utilized as model compounds of active centres in various complexes (Tamboura et al., 2009). We report here the crystal structure of the title compound ( Fig. 1).

Structure Reports Online
In the title compound,C 9 H 10 N 2 O 2 .H 2 O, (I) the molecular skeleton is nearly planar. The molecule adopts a trans configuration with respect to the C═N bond, while the side chain is slightly twisted away from the attached ring. The dihedral angle between these two essentially planar units is 9.975 (8)°. Bond lengths and angles are comparable to those observed for N'- [1-(4-methoxyphenyl)ethylidene]acetohydrazide (Li et al., 2008).
The crystal packing exhibits a three-dimensional network composed from alternating molecules of (I) and crystalline water, which interact via N-H···O, O-H···O and O-H···N hydrogen bonds. In addition, a intermolecular C-H···π interactions is observed (Table 1 and Fig 2). and refined using a riding model, with U iso (H) =1.2U eq (C,N) and 1.5U eq (C methyl ). In the absence of significant anomalous scattering effects, Friedel pairs were averaged.

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
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 > 2sigma(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.