title: Benzamidinium 2-meth-oxy-benzoate.
abstract: The title mol-ecular salt, C7H9N2 (+.)C8H7O3 (-), was synthesized by reaction between benzamidine (benzene-carboximidamide) and 2-meth-oxy-benzoic acid. In the cation, the amidinium group has two similar C-N bonds [1.3070 (17) and 1.3145 (16) Å] and is almost coplanar with the benzene ring, making a dihedral angle of 5.34 (12)°. In the anion, the meth-oxy substituent forces the carboxyl-ate group to be twisted by 69.45 (6)° with respect to the plane of the aromatic fragment. In the crystal, the components are connected by two N(+)-H⋯O(-) (±)CAHB (charge-assisted hydrogen bonds), forming centrosymmetric ionic dimers with graph-set motif R 2 (2)(8). These ionic dimers are then joined in ribbons running along the b-axis direction by another R 4 (2)(8) motif involving the remaining N(+)-H⋯O(-) hydrogen bonds. Remarkably, at variance with the well known carb-oxy-lic dimer R 2 (2)(8) motif, the carboxyl-ate-amidinium pair is not planar, the dihedral angle between the planes defined by the CN2 (+) and CO2 (-) atoms being 18.57 (12)°.
authors.affiliation: Chemistry Department, "Sapienza" University of Rome, P.le A. Moro, 5, I-00185 Rome, Italy.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Portalone
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