organic compounds
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The anion of the title salt, C6H9N2+·C6H4NO3−, undergoes an enol-to-keto tautomerism during the crystallization. In the crystal structure, the cation and anion are held together by a relatively short N—HO hydrogen bond, and the two anions are further connected to each other by a pair of N—HO hydrogen bonds with an R22(8) ring motif, thus forming a centrosymmetric 2 + 2 aggregate. The aggregates are further linked through weak N—HO and C—HO hydrogen bonds, resulting a three-dimensional network.
organic compounds
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The 3-chlorobenzoate anion of the title salt, C6H9N2+·C7H4ClO2−, is nearly planar with a dihedral angle of 2.44 (13)° between the benzene ring and the carboxylate group. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxylate O atoms of the anion via a pair of N—HO hydrogen bonds with an R22(8) ring motif, forming an approximately planar ion pair with a dihedral angle of 7.92 (5)° between the pyridinium and benzene rings. The ion pairs are further connected via N—HO and C—HO hydrogen bonds, forming a two-dimensional network parallel to the bc plane.
organic compounds
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In the 2-aminobenzoate anion of the title salt, C6H9N2+·C7H6NO2−, an intramolecular N—HO hydrogen bond is observed. The dihedral angle between the ring and the CO2 group is 8.41 (13)°. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxylate O atoms via a pair of N—HO hydrogen bonds, forming an R22(8) ring motif. The ion pairs are further connected via N—HO hydrogen bonds, resulting in a donor–donor–acceptor–acceptor (DDAA) array of quadruple hydrogen bonds. The crystal structure also features a weak N—HO hydrogen bond and a C—Hπ interaction, resulting in a three-dimensional network.