The title molecular salt, C7H9N2 +.C8H7O3 -, was synthesized by reaction between benzamidine (benzenecarboximidamide) and 2-methoxybenzoic 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 methoxy substituent forces the carboxylate 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 carboxylic dimer R 2 2(8) motif, the carboxylate-amidinium pair is not planar, the dihedral angle between the planes defined by the CN2 + and CO2 - atoms being 18.57 (12)°.
Benzamidinium 2-methoxybenzoate / Portalone, Gustavo. - In: ACTA CRYSTALLOGRAPHICA SECTION E-STRUCTURE REPORTS ONLINE. - ISSN 1600-5368. - STAMPA. - 69:7(2013), pp. o1114-o1115. [10.1107/s1600536813016395]
Benzamidinium 2-methoxybenzoate
PORTALONE, Gustavo
2013
Abstract
The title molecular salt, C7H9N2 +.C8H7O3 -, was synthesized by reaction between benzamidine (benzenecarboximidamide) and 2-methoxybenzoic 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 methoxy substituent forces the carboxylate 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 carboxylic dimer R 2 2(8) motif, the carboxylate-amidinium pair is not planar, the dihedral angle between the planes defined by the CN2 + and CO2 - atoms being 18.57 (12)°.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
