2011 Volume 27 Pages 67-68
3,8-Dibromo-3-(bromomethyl)-3,3a,4,5,6,6a-hexahydro-6a-hydroxy-6,9a-dimethylazuleno[4,5-b]furan-2,9-dione (C15H17Br3O4) crystallizes in the monoclinic space group P21 with unit-cell parameters: a = 7.9170(6)Å, b = 10.7305(6)Å, c = 10.4145(8)Å, β = 109.246(9)° and Z = 2. The crystal structure was solved by direct methods, and refined by full-matrix least-squares to a final R-value of 0.0477 for 2341 observed reflections. The seven-membered ring assumes a twist chair conformation, while the two five-membered rings exhibit envelope conformations. The ring junction A/B is trans fused, while ring junction B/C is cis fused. The characteristic pattern observed in the packing diagram has the appearance of twisted chains of molecules packed together to form layers.
