[3-Bromo-2-(3-fluorobenzyloxy)phenyl]boronic acid

In the title compound, C13H11BBrFO3, the dioxyboron fragment is close to co-planar with the benzene ring to which the B atom is connected [dihedral angle = 8.96 (4)°]. The dihedral angle between the two benzene rings is 14.8 (2)°. One of the OH groups is engaged in an intramolecular O—H⋯O hydrogen-bonding interaction. The second OH group is involved in intermolecular hydrogen bonding, forming a centrosymmetric dimer. The F atom and the corresponding meta-H atom are disordered over two positions in a 0.675 (6):0.325 (6) ratio.

In the title compound, C 13 H 11 BBrFO 3 , the dioxyboron fragment is close to co-planar with the benzene ring to which the B atom is connected [dihedral angle = 8.96 (4) ]. The dihedral angle between the two benzene rings is 14.8 (2) . One of the OH groups is engaged in an intramolecular O-HÁ Á ÁO hydrogen-bonding interaction. The second OH group is involved in intermolecular hydrogen bonding, forming a centrosymmetric dimer. The F atom and the corresponding meta-H atom are disordered over two positions in a 0.675 (6):0.325 (6) ratio.
This work was supported by Warsaw University of Technology and the Polish Ministry of Science and Higher Education (grant No. N N205 055633). The X-ray measurements were undertaken in the Crystallographic Unit of the Physical Chemistry Laboratory at the Chemistry Department of the University of Warsaw. We acknowledge the Aldrich Chemical Company for the donation of chemicals and equipment. We address our special thanks to Łukasz Dobrzycki from the University of Warsaw for many valuable suggestions regarding the data analysis.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WM2251).
The molecular structure of (I) shows that the dioxyboron fragment formed by B, O1 and O2 atoms is essentially planar with the phenyl ring to which the boron atom is connected (C6-C5-B1-O2 = 3.6 (6)°). The hydrogen atom bonded to O2 is involved in an intramolecular O-H···O interaction with atom O3, forming a five-membered ring. The hydrogen atom bonded to O1 is involved in an intermolecular hydrogen bonding to form a centrosymmetric dimer (Fig. 2). The angle between planes formed by two phenyl rings in the same molecule is 14.8 (2)°.
For the structural characterization of a related boronic acid derivative, see: Serwatowski et al. (2006).

Refinement
The fluorine atom is disordered over two positions with site occupation factors of 0.325 (6) and 0.675 (6). Positions of most of the hydrogen atoms were refined freely with U iso (H) = 1.2 or 1.5Ueq(C). The OH hydrogen atoms were refined with a constrained bond length of O-H = 0.84 Å. Hydrogen atoms that belong to the disordered part of the phenyl ring were not refined but added geometrically with a fixed bond length of 0.95 Å. Fig. 1. The molecular structure of (I), showing the atom labelling scheme. Displacement ellipsoids for all non-H atoms are drawn at the 50% probability level. H atoms are given as spheres of arbitrary radius.  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.