N′-[1-(2-Aminophenyl)ethylidene]benzohydrazide

The title compound, C15H15N3O, was obtained by a condensation reaction between o-aminoacetophenone and benzoyl hydrazine. The molecule displays an E configuration about the C=N bond. Intramolecular N—H⋯N hydrogen bonds are formed between the 2-aminophenyl and imine groups. In the crystal, dimers are formed between molecules linked by intermolecular N—H⋯O hydrogen bonds from the 2-aminophenyl group. In addition there are intermolecular N—H⋯O hydrogen bonds between the amine and carbonyl groups of adjacent molecules. The molecule is twisted rather than planar due to a steric interaction between the central amide group and the two outer benzene rings. The dihedral angles between this central group and the two rings are 23.29 (9) and 24.96 (9)°.

The title compound, C 15 H 15 N 3 O, was obtained by a condensation reaction between o-aminoacetophenone and benzoyl hydrazine. The molecule displays an E configuration about the C N bond. Intramolecular N-HÁ Á ÁN hydrogen bonds are formed between the 2-aminophenyl and imine groups. In the crystal, dimers are formed between molecules linked by intermolecular N-HÁ Á ÁO hydrogen bonds from the 2-aminophenyl group. In addition there are intermolecular N-HÁ Á ÁO hydrogen bonds between the amine and carbonyl groups of adjacent molecules. The molecule is twisted rather than planar due to a steric interaction between the central amide group and the two outer benzene rings. The dihedral angles between this central group and the two rings are 23.29 (9) and 24.96 (9) .   Table 1 Hydrogen-bond geometry (Å , ).

Comment
Hydrazones derived from the condensation reactions of hydrazides with aldehydes or ketones show excellent biological properties, such as antimicrobial, antitubercular, anticancer and antimalarial (Kocyigit-Kaymakcioglu et al., 2009;Kou et al., 2009;Mahalingam et al.., 2009;Sundaravel et al., 2009;Yin et al., 2007;Zhang et al.,2007. The hydrazones are also important for their use as plasticizers and stabilizers for polymers, polymerization initiators, antioxidants and as indicators (Gupta et al., 2007). Recently, a large number of hydrazone compounds have been reported (Qiu et al., 2008;Qiu, 2009;Ren et al., 2009). In this paper, a new hydrazone compound, derived from the condensation reaction of 2-aminoacetophenone and benzoyl hydrazine, has been reported.
The molecular structure of the title compound is shown in the fig. 1. The molecule and displays an E configuration about the C=N double bond. All bond lengths are within normal ranges (Xiao et al., 2009;Fun et al., 2008a,b). The molecular conformation is stabilized by an intramolecular N-H···.O hydrogen bond and short contact bonds (Fig. 1). In the crystal there are both inter-and intra-molecular hydrogen bonding involving the amine protons. In-plane dimers (r.m.s. deviation for N1 N2 N3 C10-C16 and equivalent atoms = 0.016 Å) are formed between molecules linked by N-H···O hydrogen bonds from the 2-aminophenyl moiety (Fig. 2). In addition there are intermolecular out of plane N-H···O hydrogen bonds between amine and carbonyl group of adjoining molecules (Fig. 3). Intramolecular N-H···N hydrogen bonds are formed between the 2-aminophenyl and imine moieties within the same molecule. The molecule is twisted rather than planar due to steric interaction between the central amide group and the two end groups. The torsion angles between this central group and the two ends are 23.29 (9) and 24.96 (9)° respectively.

Experimental
An ethanolic solution of benzoyl hydazine (50 ml, 6.8 g) was taken in a round bottom flask followed by dropwise addition of ethanolic solution of o-aminoacetophenone (50 ml, 6.05 ml) with stirring. The above solution was refluxed for 4-5 h and gave a yellow transparent solution. On keeping the solution in open air for 5-6 h in a beaker, yellow crystals of the product were obtained.

Refinement
H atoms bound to C and N atoms were located in a difference Fourier map, refined isotropically and then placed using HFIX commands in SHELXL97. All H atoms were allowed for as riding atoms with the N-H distances of 0.86 Å, and C-H

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 > 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.