3-exo-Chloro-8-oxabicyclo[3.2.1]oct-6-ene-2,4-diol chloroform 0.33-solvate

The title compound, 3C7H9ClO3·CHCl3, crystallizes with molecules of 3-exo-chloro-8-oxabicyclo[3.2.1]oct-6-ene-2,4-diol (A) and chloroform in a 3:1 ratio, in the space group R3m. Molecules of A straddle a crystallographic mirror plane, whereas the chloroform molecules (C and H atoms) lie additionally on the threefold axis. The molecules of A are linked into right- and left-helical chains by means of O—H...O hydrogen bonds, thus forming columns running along the c axis. Six interpenetrated columns form a channel in which the solvent molecules (chloroform) are located.