CRYSTAL STRUCTURE OF 2-BROMO-4-HYDROXYPYRIDINE: HYDROGEN AND HALOGEN BONDING
The crystal structure of 2-bromo-4-hydroxypyridine (1) at 120 K is reported. The compound crystallizes in the monoclinic space group C2/c with a = 15.6770(6) Å, b = 3.86471(13) Å, c = 18.0645(7) Å and β = 90.916(3)°. The compound exhibits both the 4-hydroxypyridine and 4- pyridone tautomers as exhibited by the disordered proton which occupies the O-H and N-H positions equally. Hydrogen bonding links the molecules into chains parallel to the ac-face diagonal. Halogen bonds [Br … O = 3.0809(15) Å] roughly parallel to the a-axis link the chains into layers roughly parallel to the bc-face diagonal. π-stacking interactions complete the stabilization of the structure.