3-(4-Chlorophenyl)-1-cyclopropyl-2-(2-fluorophenyl)-5-phenylpentane-1,5-dione

In the title compound, C26H22ClFO2, the cyclopropane ring is disordered over two orientations, with site-occupancy factors of 0.64 (2) and 0.36 (2). The major occupancy component of the cyclopropane ring makes dihedral angles of 47.6 (7), 50.4 (7) and 65.4 (7)° with the fluoro-, chloro- and unsubstituted benzene rings, respectively [the corresponding values for the minor occupancy component are 47.6 (12), 51.0 (12) and 60.9 (12)°]. An intramolecular C—H⋯O hydrogen bond occurs. The F and Cl atoms deviate by 0.0508 (12) and 0.0592 (7) Å from the planes of their attached benzene rings. In the crystal, C—H⋯F hydrogen bonds link the molecules into chains along the b-axis direction.


Comment
Diketones are popular in organic synthesis for their applications in biology and medicine. They are known to exhibit antioxidants, antitumour and antibacterial activities (Bennett et al., 1999). They are also key intermediates in the preparation of various heterocyclic compounds (Sato et al., 2008).
The dihedral angle between the fluoro substituted phenyl ring and the chloro substituted phenyl ring is 6.50 (9)° and the dihedral angle between the fluoro substituted phenyl ring and the unsubstituted phenyl ring is 64.52 (10)°. The dihedral angle between the chloro substituted phenyl ring and the unsubstituted phenyl ring is 70.89 (10)°. The chlorine atom (Cl1) attached with the phenyl ring deviates by 0.0592 (7)Å. The packing of the crystal is stabilized by C-H···F hydrogen bonds.
Yield=96%, melting point = 418-421 K. Single crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the title compound in ethanol at room temperature.

Refinement
The cyclopropane ring was disordered over two positions with the site occupancy factors of 0.64 (2):0.36 (2). The bond distances of the disordered components were restrained using standard similarity restraints SADI [SHELXL97, Sheldrick, 2008] with s.u. of 0.01 Å. The hydrogen atoms were placed in calculated positions with C-H = 0.93 to 0.98 Å and refined in the riding model with fixed isotropic displacement parameters: U iso (H) = 1.5U eq (C) for methyl group and U iso (H) = 1.2U eq (C) for other groups.   The crystal packing of the title compound viewed down b axis. H-atoms not involved in H-bonds have been excluded for clarity.

3-(4-Chlorophenyl)-1-cyclopropyl-2-(2-fluorophenyl)-5-phenylpentane-1,5-dione
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 > 2sigma(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 Occ.