(E)-1-(3-Bromophenyl)-3-(3,4-dimethoxyphenyl)prop-2-en-1-one

The molecular structure of the title compound, C17H15BrO3, consists of a bromophenyl and a 3,4-dimethoxyphenyl group linked through a prop-2-en-1-one spacer. The C=C double bond displays an E conformation, while the carbonyl group shows an S-cis conformation relative to the double bond.

The molecular structure of the title compound, C 17 H 15 BrO 3 , consists of a bromophenyl and a 3,4-dimethoxyphenyl group linked through a prop-2-en-1-one spacer. The C C double bond displays an E conformation, while the carbonyl group shows an S-cis conformation relative to the double bond.

Experimental
The molecular structure of the title compound displays two phenyl rings connected through the organic prop-2-en-1-one spacer. As shown in Fig. 1, one phenyl ring is substituted at positions 3 and 4 with methoxy groups, while the other is substituted at position 3′ with one Br atom.
The dihedral angle between the two aromatic rings joined by the conjugated spacer is 26.59 (9)°. On the other hand, the spacer formed by C10-C9-C8-C7-O1-C1 can be considered as a plane with a RMSD of 0.029 Å. This feature is also observed in other chalcones (Escobar et al. 2008;Valdebenito et al., 2010;Chu et al. 2004;Radha Krishna et al. 2005;Wu et al. 2005).
Finally, both inter-and intramolecular hydrogen bonds are not observed in the crystalline packing of title compound.

Experimental
A mixture of 3-bromoacetophenone (0.5 g, 2,5 mmol) and 3,4-dimethoxibenzaldehyde (0.41 g, 2,5 mmol), were dissolved in Methanol (50 ml), and were treated with KOH (2 g, dissolved in 20 ml methanol). After 20 min 30 ml of water were added, and the title compound precipitated as a yellow solid. Then, it was filtered and recrystallized in ethanol

Refinement
The H atoms positions were calculated after each cycle of refinement using a riding model with C-H distances in the range 0.95-0.98 Å and U iso (H) = 1.2-1.5U eq (C).

Computing details
Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).  The molecular structure of title compound with full atom numbering scheme. Displacement ellipsoids are presented at 30% probability level and H atoms are shown as spheres. Special details Experimental. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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.