1-Bromo-2-chloro-4,5-dimethoxybenzene

The two methoxy groups of the title compound, C8H8BrClO2, are approximately coplanar with the benzene ring, the dihedral angles in all four molecules in the asymmetric unit ranging from of 0.9 (3) to 12.3 (3)°. All four independent molecules are disordered by different amounts about non-crystallographic twofold axes which nearly superimpose the Cl and Br sites.

The two methoxy groups of the title compound, C 8 H 8 BrClO 2 , are approximately coplanar with the benzene ring, the dihedral angles in all four molecules in the asymmetric unit ranging from of 0.9 (3) to 12.3 (3) . All four independent molecules are disordered by different amounts about noncrystallographic twofold axes which nearly superimpose the Cl and Br sites.

Experimental
The title compound was synthesized by chlorination of 1-bromo-3,4-dimethoxy-benzene with HCl/H 2 O 2 as chlorination reagent as described previously (Song et al., 2008). Crystals suitable for X-ray diffraction were grown by slow evaporation of a saturated solution of the title compound in CHCl 3 .  Fig. 1. One of the four independent molecules of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. Only the major disorder component is shown.

Special details
Experimental. The triclinic cell appears to transform to a C-centered monoclinic cell but the data fail to merge in a satisfactory way in that setting. The structure solved and refined well with the triclinic setting in spite of the extensive disorder. The refined model does not transform to any monoclinic C model either manually or by use of missed symmetry algorithms such as ADDSYM as implemented in Platon (Spek).
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 > 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.