(5-Bromo-2-hydroxyphenyl)(4-propylcyclohexyl)methanone

In the title compound, C16H21BrO2, the cyclohexane ring adopts a chair conformation. The hydroxy and carbonyl groups are involved in an intramolecular O—H⋯O hydrogen bond. In the crystal, weak C—H⋯O interactions link the molecules into zigzag chains along [010].

In the title compound, C 16 H 21 BrO 2 , the cyclohexane ring adopts a chair conformation. The hydroxy and carbonyl groups are involved in an intramolecular O-HÁ Á ÁO hydrogen bond. In the crystal, weak C-HÁ Á ÁO interactions link the molecules into zigzag chains along [010].

Experimental
In (I) (Fig. 1), all bond lengths and angles are normal and in a good agreement with those reported previously for related compounds (Robinson et al., 2002;Wang et al., 2011). The cyclohexane ring (C8-C13) adopts a chair conformation.

Experimental
A dried 100-ml round-bottomed flask was charged with 1.89 g (10 mmol) of trans-4-propylcyclohexanecarboxylic acid chloride, 1.87 g (10 mmol) of 4-bromoanisole and 20 ml of dried dichloromethane. The mixture was stirred on an icewater bath, followed by addition of 1.60 g (12 mmol) of anhydrous aluminium chloride in a portionwise manner. After addition, the reaction mixture was stirred at room temperature for 1 h and at reflux overnight, and poured into 300 ml of ice-water. The mixture thus formed was exacted with three 50-ml portions of dichloromethane, and the combined exacts were washed with saturated brine, dried over sodium sulfate and evaporated on a rotary evaporator to afford the crude title compound. Pure title compound was obtained by column chromatography. Crystals suitable for X-ray diffraction were obtained through slow evaporation of a solution of the pure title compound in dichloromethane/petroleum ether (1/30 by volume).

Refinement
Hydroxy atom H1 was located on a difference map and isotropically refined. C-boundl H atoms were geometrically positioned [C-H = 0.95-1.00 Å], and included in the final cycles of refinement using a riding model, with U iso (H) = 1.2U eq (C) and 1.5U eq (C) for the methyl H atoms.

Computing details
Data collection: CrystalClear-SM Expert (Rigaku/MSC, 2009); cell refinement: CrystalClear-SM Expert (Rigaku/MSC, 2009); data reduction: CrystalClear-SM Expert (Rigaku/MSC, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008  View of the title compound, with displacement ellipsoids drawn at the 40% probability level. Special details 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.