N′-(3,5-Dichloro-2-hydroxybenzylidene)-3-methoxybenzohydrazide methanol solvate

In the title compound, C15H12Cl2N2O3·CH3OH, the Schiff base molecule is nearly planar, with a dihedral angle of 4.5 (2)° between the two benzene rings. An intramolecular O—H⋯N hydrogen bond is observed. The methanol solvent molecule is linked to the Schiff base molecule through intermolecular N—H⋯O and O—H⋯O hydrogen bonds.

In the title compound, C 15 H 12 Cl 2 N 2 O 3 ÁCH 3 OH, the Schiff base molecule is nearly planar, with a dihedral angle of 4.5 (2) between the two benzene rings. An intramolecular O-HÁ Á ÁN hydrogen bond is observed. The methanol solvent molecule is linked to the Schiff base molecule through intermolecular N-HÁ Á ÁO and O-HÁ Á ÁO hydrogen bonds.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI2593).

Comment
Schiff base compounds can be easily synthesized from the reaction of aldehydes with primary amines (Herrick et al., 2008;Suresh et al., 2007;Liu et al., 2007). These compounds show interesting biological activities, especially antimicrobial activities (Bhandari et al., 2008;Sinha et al., 2008;Sun et al., 2008). Recently, the crystal structures of a few Schiff base compounds obtained from the derivatives of salicylaldehyde with benzohydrazide have been reported (Wang et al., 2008;Tang, 2008a,b;Yang & Zheng, 2007). We report here the crystal structure of a new Schiff base compound, derived from 3,5-dichlorosalicylaldehyde and 3-methoxybenzohydrazide.
The asymmetric unit consists of a Schiff base molecule and a methanol molecule of crystallization (  (Table 1 and Fig.2).
Experimental 3,5-Dichlorosalicylaldehyde (0.1 mmol, 19.0 mg) and 3-methoxybenzohydrazide (0.1 mmol, 16.6 mg) were dissolved in methanol (20 ml). The mixture was stirred at room temperature to give a clear yellow solution. Yellow block-shaped crystals were formed after a week.

Refinement
Atom H2 was located in a difference Fourier map and refined isotropically, with the N2-H2 distance restrained to 0.90 (1) Å, and with U iso (H) set to 0.08 Å 2 . All other H atoms were constrained to idealized geometries, with C-H = 0.93-0.96 Å, O-H = 0.82 Å, and with U iso (H) = 1.2U eq (C) and 1.5U eq (O and methyl C). A rotating group model was used for the methyl and hydroxyl groups. Fig. 1

Special details
Geometry. All e.s. 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 Rfactors(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.