Tramadolium 2-chlorobenzoate

In the title molecular salt, C16H26NO2+·C7H4ClO2−, {systematic name: [2-hydroxy-2-(3-methoxyphenyl)cyclohexylmethyl]dimethylammonium 2-chlorobenzoate}, the cyclohexane ring of the cation exhibits a chair conformation with the aromatic and amine substituents in equatorial orientations and the hydroxyl group in an axial orientation. In the anion, the dihedral angle between the aromatic ring and the carboxylate group is 39.16 (13)°. In the crystal, the cations are linked to the anions by O—H...O, N—H...O and C—H...O hydrogen bonds, generating [010] chains. Further C—H...O and C—H...π interactions are also observed, which link the chains into a three-dimensional framework.