Halogen Bonds in the Structure of Tetrabromophenylbutane

The crystal structure of 1,2,3,4-tetrabromo,1-phenylbutane determined by single crystal synchrotron X-ray diffraction is described. Molecules of the compound compose a layered structure of the Langmuir-Blodgett film type (with tail-to-tail, head-to-head orientations of molecules of the neighboring layers) in which phenyl radicals of one layer contact with those of another. Halogen bonds and BrMIDLINE HORIZONTAL ELLIPSISBr contacts (four per each molecule) have the key importance for the molecular packing in the layer. The distance between bromine atoms in these bonds and contacts is 3.656-4.002 angstrom. The thermal analysis shows that the tetrabromophenylbutane melting point is 148 degrees C, with the compound starting to decompose at 150-280 degrees C in one step with releasing HBr and benzene.