N′-Benzylidene-2-chloro-N-(4-chlorophenyl)acetohydrazide

In the title compound, C15H12Cl2N2O, the atoms not making up the chlorobenzene ring are approximately coplanar (r.m.s. deviation = 0.073 Å). The dihedral angle between these 13 atoms and the chlorobenzene ring is 67.37 (10)°. The C=O and Csp 2—Cl groups are almost eclipsed [Cl—C—C=O = −6.5 (3)°]. In the crystal, C(6) chains linked by C—H⋯O hydrogen bonds result in [100] chains.


Comment
Schiff bases are important class of compounds in medicinal chemistry, showing e.g.: antimicrobal (Shyma et al., 2013), and anticonvulsant (Nithinchandra et al., 2013) activities. As part of our studies in this area, we now describe the structure of the title compound, (I), (Fig. 1).
The dihedral angle between the benzene ring is 63.18° (13) and the molecules are linked to one another with hydrogen bonds C3-H3···O1 (Table 1, Fig. 2) along a-axis.

Experimental
4-Chlorophenylhydrazine (0.01 mol) was stirred with benzaldehyde (0.01 mol) in methanol (10 mL) in presence of few drops of acetic acid. The resulting precipitate was filtered and washed with chilled methanol and dried. The resulting Schiff base, 1-benzylidene-2-(4-chlorophenyl)hydrazine (0.01 mol) and triethylamine (0.01 mol) was taken in dioxane solvent. Chloroacetylchloride (0.01 mol) was added to the above mixture at 0-5°C. After completion of the reaction, the mixture was poured on to ice cold water. The precipitated solid was filtered, washed with water and recrystallized from ethanol. Brown blocks were obtained from a 1:2 mixture of DMF and ethanol solution by slow evaporation.

Refinement
All the H atoms were fixed geometrically (C-H= 0.93-0.96 Å) and allowed to ride on their parent atoms with U iso (H) =1.5U eq (C-methyl) and = 1.2U eq (C) for other H atoms.

N′-Benzylidene-2-chloro-N-(4-chlorophenyl)acetohydrazide
Crystal data  (10) Special details Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement on F 2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses 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 observed criterion of F 2 > σ(F 2 ) is used only for calculating -R-factor-obs 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Cl1 0.88967 (18