Acta Crystallographica Section B

Structural Science

Volume 55, Part 6 (December 1999)

research papers

Acta Cryst. (1999). B55, 1005-1013 [ doi:10.1107/S0108768199005911 ]

A comparative study of the crystal structures of tetrahalogenated hydroquinones and -hydroquinone

V. R. Thalladi, H.-C. Weiss, R. Boese, A. Nangia and G. R. Desiraju

Abstract: [gamma] -Hydroquinone (1) and its tetrafluoro, tetrachloro and tetrabromo derivatives (2), (3) and (4) adopt crystal structures that have an almost invariant system of O-HO hydrogen bonds. However, within this O-HO framework, the four structures display variations that are characteristic of the C-H, C-F, C-Cl and C-Br groups. In the parent compound (1) aromatic rings are packed with a herringbone geometry, whilst in the halogenated derivatives (3) and (4), polarization-type halogenhalogen contacts are optimized. The fluoro derivative (2) is exceptional in that neither of the above possibilities is adopted, even though the O-HO scaffolding does not per se prohibit either of them geometrically.

Keywords: Hydroquinone; Comparative study; Tetrahalogenated derivatives; Hydrogen bonding.