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 Br⋯Br 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 Å. The thermal analysis shows that the tetrabromophenylbutane melting point is 148 °C, with the compound starting to decompose at 150-280 °C in one step with releasing HBr and benzene.