The three-dimensional structural characterization of hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) Original Research Article

The 1H NMR spectrum and the crystal structure of HCDBCO [(1R,2R,5R,6R,9S,10S)-5,6-dibromo-1,10,11,12,13,13-hexachlorotricyclo[8,2,1,02,9]-tridec-11-ene)] are reported. The measured dihedral angles from the X-ray structure correlate very well with those calculated from the proton–proton coupling constants indicating that the conformations in solution and in the solid state are probably very similar. Attempts at calculating the 3D model structure of HCDBCO only produced a very poor match between the measured dihedral angles between vicinal protons and the observed proton–proton coupling constants from the 1H NMR spectrum. GC/MS analysis with an injector temperature of 250 °C produced minor amounts of debrominated HCDBCO. Reducing the temperature to 200 °C eliminated this problem.