2,4-Dibromo-6-{[(5-chloro-2-methylphenyl)imino]methyl}phenol

In the molecular structure of the title Schiff base, C14H10Br2ClNO, the chlorophenyl ring and dibromophenol ring are almost coplanar; the dihedral angle between the planes of the two rings is 10.50 (18)°. There is an intramolecular O—H⋯N hydrogen bond, with an O⋯N distance of 2.576 (4)Å. The crystal structure is stabilized by π–π stacking of neighbouring aromatic rings along the b-axis direction [centroid–centroid distance = 3.6896 (5) Å].

In the molecular structure of the title Schiff base, C 14 H 10 Br 2 ClNO, the chlorophenyl ring and dibromophenol ring are almost coplanar; the dihedral angle between the planes of the two rings is 10.50 (18) . There is an intramolecular O-HÁ Á ÁN hydrogen bond, with an OÁ Á ÁN distance of 2.576 (4)Å . The crystal structure is stabilized bystacking of neighbouring aromatic rings along the b-axis direction [centroid-centroid distance = 3.6896 (5) Å ].   Table 1 Hydrogen-bond geometry (Å , ).

References
Atalay, Ş., Erdem, T. K., Erşahinb, F. & Tınkılıç, N. (2008). Acta Cryst., E64, o92. Bruker (2004). longer than that of C-Cl at 1.744 (4)Å due to the radius of Br atom is bigger than that of Cl atom. It is noteworthy to note that H1 atom bonded to O1 is involved in O1-H1···N1 intramolecular hydrogen bond, which resulted in formation of sixmembered ring (O1-H1···N1═C8-C9-C10) (Fig. 1). The dibromophenol ring is almost coplanar with the chlorophenyl ring with the dihedral angle between the two planes is 10.50 (18)°. Furthermore, the aromatic ring in the molecule is nearly parallel to the aromatic ring of its neighboring molecule with a ring-to-ring distance of 3.4715 (5)Å (3.6896 (5)Å) and an off-centre angle of 21.98°, indicating a weak π···π stacking interaction between the aromatic rings (Fig. 2). The packing diagram of the title compound shown stacks are arranged in a centrosymmetric manner and a C 2 axis passing through the middle point of ac plane (Fig. 3).

Experimental
A mixture of 5-chloro-2-methylaniline (1.42 g, 10 mmol), 3,5-dibromo-2-hydroxybenzaldehyde (2.80 g, 10 mmol) in 50 ml CH 2 Cl 2 was refluxed under an Ar atmosphere for about 6 h to yield a yellow precipitate. The product was collected by filtration and washed with cold ethanol to give Schiff base compoud in 92.2% yield (3.55 g). The yellow single crystals suitable for X-ray analysis were grown from CH 2 Cl 2 / absolute ethanol (3 / 2) systems by slow evaporation of the solvents at room temperature over a period of about one week.

Refinement
Hydrogen atoms for the carbon atoms were placed in geometrically idealized positions and constrained to ride on their parent with C-H = 0.96Å and 0.93Å for methyl and aryl type H-atoms, respectively, and refined in a riding mode with U iso (H) = 1.2U eq (C) for aromatic H and U iso (H) = 1.5U eq (C) for methyl H.   The π···π stacking of the title compound along the b axis.

Figure 3
A packing diagram of the title compound, viewed along the b axis, showing the centrosymmetric arrangement. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.41 e Å −3 Δρ min = −0.37 e Å −3 Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 R-factors(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.

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