(R)-Doxylaminium (R,R)-tartrate

Abstract

In the title compound (systematic name: (R)-dimethyl{2-[1-phenyl-1-(pyridin-2-yl)ethoxy]ethyl}azanium (R,R)-3-carboxy-2,3-dihydroxypropanoate), C17H23N2O+·C4H5O6−, the doxylaminium cation is protonated at the N atom. The tartrate monoanions are linked by short, almost linear O—H...O hydrogen bonds into chains extended along [100]. These chains are interlinked by anion–pyridine O—H...N hydrogen bonds into a two-dimensional grid structure. WeakC—H...O interactions also play a role in the crystal packing. An intramolecular hydroxy–carboxylate O—H...O hydrogen bond influences the conformation of the anion: the hydrogen-bonded fragment is almost planar, the maximum deviation from the mean plane being 0.059 (14) Å. In the cation, the aromatic rings are almost perpendicular [dihedral angle = 84.94 (8)°] and the conformation of the O—C—C—N chain isgauche(−), the dihedral angle is −76.6 (2)°. The absolute configuration was assigned on the basis of known chirality of the parent compound.