2-(2-{2-[2-(Dibromomethyl)phenoxy]ethoxy}benzyloxy)benzaldehyde

The molecule of the title compound, C23H20Br2O4, adopts a Z conformation as a result of intermolecular C—H⋯Br bonding. One benzene ring, with the structure R-CHBr2, makes a dihedral angle of 63.0 (2)° with the other benzene ring attached to the aldehyde group. Intermolecular π–π stacking interactions [centroid–centroid distance = 3.698 (4) Å] and a weak C—H⋯Br contact is present in the crystal structure.

In the title compound (Fig. 1), a dihedral angle 63.0 (2)° is observed between benzene rings on the both ends of molecule.
The crystal structure is stabilized by weak intramolecular C-H···O bonds.
The molecule of the title compound is linked by the C-H···Br bonding (Fig. 2) in to the Z formation.

Experimental
All reagents and solvents were obtained from commercial sources and needed to be further purified. The title compound was synthesized according to the related literature (Purushothaman & Raghunathan, 2009). A solution of salicylaldehyde (2 mmol in 10 ml acetone) was slowly added dropwise to a suspension of 1,2-bis(2-(bromomethyl)phenoxy) ethane (1 mmol in 20 ml acetone) prepared according to the reported method (Zhang et al., 2010) and anhydrous potassium carbonate (2 mmol). The mixture was refluxed for 8 h. The reaction mixture was then cooled to room temperature and filtered. After this period, the residue was dissolved and extracted by ethyl acetate. The combined organical layer was washed with water and then dried with anhydrous sodium sulfate. After that the solvent was evaporated under vacuum to give the product.
The obtained residue was purified by flash column chromatography on silica gel using petroleum ether/ethylacetate (5:2) mixtures as eluent.

Refinement
All H atoms were found from difference Fourier maps and were subsequently refined in a riding-model approximation with C-H distances ranging from 0.93Å to 0.98Å and with U iso (H) = 1.2 U eq (C) of the carrier atom. Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as a small spheres of arbitrary radius.

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 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.