Racemic mefloquinium chloro­difluoro­acetate: crystal structure and Hirshfeld surface analysis

In the racemic title mol­ecular salt, C(17)H(17)F(6)N(2)O(+)·C(2)ClF(2)O(3) (−) (systematic name: 2-{[2,8-bis­(tri­fluoro­meth­yl)quinolin-4-yl](hy­droxy)meth­yl}piperidin-1-ium chloro­difluoro­acetate), the cation, which is protonated at the piperidine N atom, has the shape of the letter, L, with the piperidin-1-ium group being approximately orthogonal to the quinolinyl residue [the C(q)—C(m)—C(m)–N(a) (q = quinolinyl; m = methine; a = ammonium) torsion angle is 177.79 (18)°]. An intra­molecular, charge-assisted ammonium-N—H⋯O(hydrox­yl) hydrogen bond ensures the hy­droxy-O and ammonium-N atoms lie to the same side of the mol­ecule [O(h)—C(m)—C(m)—N(a) (h = hydrox­yl) = −59.7 (2)°]. In the crystal, charge-assisted hydroxyl-O—H⋯O(−)(carboxyl­ate) and ammonium-N(+)—H⋯O(−)(carboxyl­ate) hydrogen bonds generate a supra­molecular chain along [010]; the chain is consolidated by C—H⋯O inter­actions. Links between chains to form supra­molecular layers are of the type C—Cl⋯π(quinolinyl-C(6)) and the layers thus formed stack along the a-axis direction without directional inter­actions between them. The analysis of the calculated Hirshfeld surface points to the dominance of F⋯H contacts to the surface (40.8%) with significant contributions from F⋯F (10.5%) and C⋯F (7.0%) contacts.