3-Chloro-N′-(3-ethoxy-2-hydroxybenzylidene)benzohydrazide monohydrate

In the title compound, C16H15ClN2O3·H2O, the water molecule is linked to the Schiff base molecule via an O—H⋯O hydrogen bond. In the Schiff base molecule, an intramolecular O—H⋯N hydrogen bond occurs and the dihedral angle between the two benzene rings is 20.5 (5)°. In the crystal, the Schiff base and water molecules are linked by intermolecular N—H⋯O and O—H⋯O hydrogen bonds, forming layers in the ab plane.

In the title compound, C 16 H 15 ClN 2 O 3 ÁH 2 O, the water molecule is linked to the Schiff base molecule via an O-HÁ Á ÁO hydrogen bond. In the Schiff base molecule, an intramolecular O-HÁ Á ÁN hydrogen bond occurs and the dihedral angle between the two benzene rings is 20.5 (5) . In the crystal, the Schiff base and water molecules are linked by intermolecular N-HÁ Á ÁO and O-HÁ Á ÁO hydrogen bonds, forming layers in the ab plane.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: OM2396).

Comment
In the last few years, a number of Schiff bases derived from the reaction of aldehydes with benzohydrazides were prepared and structurally characterized (Bessy et al., 2006;Podyachev et al., 2007;Raj & Kurup, 2007;Pouralimardan et al., 2007;Bacchi et al., 2006;Dinda et al., 2002). As a continuation of the work, in the present paper, the title new Schiff base compound, Fig. 1, is reported.
The compound contains a Schiff base molecule and a water molecule of crystallization. The water molecule is linked to the Schiff base molecule via intermolecular O-H···O hydrogen bonds (Table 1). In the Schiff base molecule, there is an O-H···N hydrogen bond, which contributes to the planarity of the molecule. The dihedral angle between the two benzene rings is 20.5 (5)°. All the bond lengths are within normal values (Allen et al., 1987). The molecules are linked through intermolecular N-H···O and O-H···O hydrogen bonds (Table 1) to form two-dimensional layers along the ab plane ( Fig. 2).

Experimental
The compound was prepared and crystallized according to the literature method (Zhu, 2010). 3-Ethoxy-2-hydroxybenzaldehyde (0.166 g, 1 mmol) and 3-chlorobenzohydrazide (0.171 g, 1 mmol) were dissolved in 30 ml 95% ethanol. The mixture was stirred at reflux for 10 min, and cooled to room temperature. The clear colorless solution was left to slow evaporation in air for a week, yielding colorless block-shaped crystals, which were collected by filtration and washed with ethanol.

Refinement
The amino and water H atoms were located from a difference Fourier map and refined isotropically, with the N-H, O-H, and H···H distances restrained to 0.90 (1), 0.85 (1), and 1.37 (2) Å, respectively. The other H atoms were positioned geometrically and refined using the riding-model approximation, with C-H = 0.93-0.97 Å, and O-H = 0.82 Å, and U iso (H) = 1.2U eq (C) or U iso (H) = 1.5U eq (C8 and O2). Fig. 1. The molecular structure of the title compound with 30% probability displacement ellipsoids for non-hydrogen atoms. Hydrogen bonds are drawn as dashed lines.