The crystal structure of the title compound was determined (crystal data at 143K: triclinic, space group P-1, Z=4, a=9.538(2)Å, b=11.638(2)Å, c=14.473(2)Å, α=88.647(3) o , β=89.875(3) o , γ=83.835(3) o , V=1596.9(4)Å 3 ). In the crystal there exist two kinds of tetrameric O-H...O hydrogen-bond (H-bond) systems that are quite similar to each other. The oxygen atoms accept also intermolecular C-H...O H-bonds. The two types of the H-bonds connect the molecules to an infinite two-dimensional supramolecular unit, the stacking of which is aided by an intermolecular C-H...π H-bond. A phase transition with ΔH t =4.4+/-0.1kJ/mol was found at around 420K.