The crystal structure of 10-bromoanthrone

Crystals of 10-bromoanthrone are triclinic, space group PT, with a=7"304 (1), b=7-768 (1), c= 11.358 (1)~, e=90.33 (1), ,8=104.58 (1), y= 116.83 (1) °, Z=2. Approximately 2300 intensities were collected on a Pailred diffractometer from a crystal mounted along a. The structure was derived by direct phasing methods and refined by full-matrix least-squares calculations. Final refinement led to an R of 0.061 and standard deviations in the range 0.003-0.006 ,~ in the positions of the heavy atoms. The molecule, whose symmetry is very close to m, exhibits a 'butterfly' shape: the planes of the two outer rings make a dihedral angle of 164 °. The most salient details of the molecular geometry are the long C(10)-Br distance of 2.032 (4) ,~, and the boatlike configuration of the central ring, the atoms C(10) and C