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Updated: Mar 25, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Crystal structure of 4,4'-di-bromo-2',5'-dimeth-oxy-[1,1'-biphen-yl]-2,5-dione (BrHBQBr)
Joseph E Meany1, Steven P Kelley1, Robert M Metzger1
1Department of Chemistry, The University of Alabama, Box 870336, Tuscaloosa, AL 35487-0336, USA.
Abstract:
In the title compound, C14H10Br2O4, the dihedral angle between the aromatic rings is 67.29 (19)°. Both meth-oxy-group C atoms lie close to the plane of their attached ring [deviations = -0.130 (4) and 0.005 (5) Å]. In the crystal, mol-ecules pack in a centrosymmetric fashion and inter-act via a mixture of weak π-π stacking inter-actions [centroid-centoid separations = 4.044 (2) and 4.063 (3) Å], weak C-H⋯O hydrogen bonding, and Br⋯Br halogen bonding. This induces a geometry quite different than that predicted by theory.
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