Acta Cryst. (2009). E65, o1275  [ doi:10.1107/S1600536809017036 ]

Low-temperature redetermination of benzofurazan 1-oxide

S. W. Ng

Abstract: In the six-membered ring of the low-temperature crystal structure of benzofurazan 1-oxide, C₆H₄N₂O₂, the two C atoms adjacent to the N atoms are linked by a delocalized aromatic bond [1.402 (2) Å]; each is connected to its neighbour by a longer, more localized, bond [1.420 (2), 1.430 (2) Å]. However, the next two bonds in the ring approximate double bonds [1.357 (2), 1.366 (2) Å]. As such, the six-membered ring is better described as a cyclohexadiene system, in contrast to the description in the room-temperature structure reported by Britton & Olson (1979) [Acta Cryst. B35, 3076-3078].

Online 14 May 2009

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