8-Hy­droxy-5-(hy­droxy­meth­yl)quinolin-1-ium chloride

The title compound, C₁₀H₁₀NO₂⁺·Cl⁻, contains a quinoline ring system which is essentially planar, with the largest deviation from the mean plane being 0.017 (1) Å. In the crystal, the ion pairs and their inversion-symmetry-related partners are linked by N—H...Cl and O—H...Cl hydrogen bonds to form tetramers which are further connected through O—H...O hydrogen bonds, building infinite one-dimensional chains parallel to the [010] direction.