A racemic mixture of the title compound, C26H26Br2, a brominated [4]helicene, crystallizes, forming columns of stacked molecules.There are two crystallographically unique molecules in the asymmetric unit, socialstudiesscholar.com both with the same helical handedness.As is typical with helicene congeners, the unique molecules show short interatomic contacts between H atoms at the read more fjord region, with H.H distances of 1.
87 and 1.94 Å.Molecules with the same helical handedness segregate in the crystal packing, forming homochiral columns.The stacked molecules are piled in a column with alternate orientations.
The shortest C.C distance in the stacked molecules is 3.306 (4) Å.