N′-(5-Bromo-2-hydroxybenzylidene)-4-nitrobenzohydrazide methanol monosolvate

In the title compound, C14H10BrN3O4·CH4O, the benzohydrazide molecule is nearly planar [maximum deviation = 0.110 (2) Å]. The mean planes of the two benzene rings make a dihedral angle of 8.4 (3)°. In the benzohydrazide molecule, there is an intramolecular O—H⋯N hydrogen bond and the NH group is hydrogen bonded to the methanol solvent molecule. In the crystal, intermolecular O—H⋯O hydrogen bonds involving the methanol solvent molecule link the benzohydrazide molecules to form chains which propagate along the a axis.

In the title compound, C 14 H 10 BrN 3 O 4 ÁCH 4 O, the benzohydrazide molecule is nearly planar [maximum deviation = 0.110 (2) Å ]. The mean planes of the two benzene rings make a dihedral angle of 8.4 (3) . In the benzohydrazide molecule, there is an intramolecular O-HÁ Á ÁN hydrogen bond and the NH group is hydrogen bonded to the methanol solvent molecule. In the crystal, intermolecular O-HÁ Á ÁO hydrogen bonds involving the methanol solvent molecule link the benzohydrazide molecules to form chains which propagate along the a axis.
In addition, benzohydrazide compounds have also been used as versatile ligands in coordination chemistry (El-Dissouky et al., 2010, Zhang et al., 2010. As a contribution to a structural study on hydrazone compounds, we present here the crystal structure of the title compound, that was obtained as the product of the reaction of 5-bromosalicylaldehyde with 4-nitrobenzohydrazide in methanol. The title compound contains a benzohydrazide molecule and a methanol solvent molecule of crystallization ( Fig. 1). In the benzohydrazide molecule there is an intramolecular O-H···N hydrogen bond and NH group is hydrogen bonded to the methanol solvate molecule. The bond distances (Allen et al., 1987) and angles are within normal ranges and agree well with the corresponding bond distances and angles reported in closely related compounds (Suleiman Gwaram et al., 2010;Dai & Mao, 2010;Ban, 2010). The benzohydrazide molecule is nearly planar [maximum deviation of 0.110 (2) Å], with the mean planes of the two benzene rings making a dihedral angle of 8.4 (3)°.
In the crystal, intermolecular O-H···O hydrogen bonds involving the methanol solvate molecule link the benzohydrazide molecules to form chains which propagate along along the a axis direction (Table 1, Fig. 2).

Experimental
To a methanol solution (20 ml) of 5-bromosalicylaldehyde (0.1 mmol, 20.1 mg) and 4-nitrobenzohydrazide (0.1 mmol, 18.1 mg), a few drops of acetic acid were added. The mixture was refluxed for 1 h and then cooled to room temperature. The white crystalline solid was collected by filtration, washed with cold methanol and dried in air. Single crystals, suitable for X-ray diffraction, were obtained by slow evaporation of a methanol solution of the product in air.

Refinement
The NH H-atom was located in a difference Fourier map and was refined with a distance restraint, N-H = 0.90 (1) Å, and U iso (H) = 0.08 Å 2 . The OH and C-bound H atoms were positioned geometrically and refined using a riding model: O-H = 0.82 Å, C-H = 0.93 and 0.96 Å, for CH and CH 3 H-atoms, respectively, with U iso (H) = k × U eq (O,C) where k = 1.5 for OH and CH 3 H-atoms and k = 1.2 for all other H-atoms.