2,7-DIMETHYL-3,5-OCTADIYNE-2,7-DIOL DICHLOROMETHANE SOLVATE - A CLATHRATE COMPRISING HYDROGEN-BONDED SUPRAMOLECULAR TUNNELS CONTAINING DICHLOROMETHANE GUEST MOLECULES

The title molecule, C10H14O2.0.06CH2Cl2, forms an unusual tubular stru cture in which double-walled channels of approximately 5 angstrom inte rnal diameter extend throughout the crystal. Groups of three molecules are positioned around a threefold axis to form a section of the tube. These molecules are configured so that methyl and acetylene groups li ne the tube and hydroxyl groups form the outer wall. As each hydroxyl group is near to a threefold screw axis, the channel walls are reinfor ced by infinite hydrogen-bonded columns parallel to c [O ... O 2.68 (1 ). 2.771 (9) angstrom]. Although dichloromethane fits well in the chan nels, the final guest-to-host ratio of 0.06:1 indicates that the open structure is unable to retain these molecules in ambient conditions.