1-(2,3-Dihydroxypropyl)-4-{2-[4-(dimethylamino)phenyl]vinyl}pyridinium chloride

The title compound, C18H23N2O2+·Cl−, crystallizes with two independent cations and anions per cell. Each cation has twofold rotational disorder about the linking vinyl groups but with unequal occupancies [0.963 (5):0.037 (5) and 0.860 (8):0.140 (8)]. The two independent cations are close to being related by an inversion centre but the data does not support the expected centrosymmetric space-group assignment. The conclusion is that the differing rotational disorder has lead to an overall non-centrosymmetric lattice. In the crystal, the molecules pack in layers parallel to (133) and (-13-3), chain-linked with motif C12(7) by the dihydroxypropyl O–H...Cl...H–O hydrogen bonds. Other lattice binding is provided by O—H...Cl, C—H...Cl and C—H...N interactions.