title: 4,4'-Bipyridine-3-nitro-benzoic acid (1/2).
abstract: The title compound, C(10)H(8)N(2)·2C(7)H(5)NO(4),was obtained unintentionally as the harvested product of the hydro-thermal reaction between Co(OAc)(2)·4H(2)O and 4,4'-bipyridine in the presence of 3-nitro-phthalic acid. In the reaction, 3-nitro-phthalic acid is transformed into 3-nitro-benzoic acid by an in situ deca-rboxylation reaction, in which the carboxyl-ate group is not deprotonated and is uncoordinated. In the crystal, the uncoordinated 3-nitro-benzoic acid and free 4,4'-bipyridine mol-ecules are linked alternately by O-H⋯N hydrogen bonds into chains, which are assembled by C-H⋯O hydrogen bonds into a three-dimensional supra-molecular network.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhu
authors.forename: Feng-Qin
authors.initials: FQ
authors.lastname: Wang
authors.forename: Yong-Nan
authors.initials: YN
authors.lastname: Zhao