title: rac-4-[4-Cyano-2-(hy-droxy-meth-yl)phen-yl]-4-(4-fluoro-phen-yl)-4-hy-droxy-N,N-dimethyl-butanaminium hemifumarate.
abstract: In the title salt, C(20)H(24)FN(2)O(2) (+)·0.5C(4)H(2)O(4) (2-), the fumarate anion is located on an inversion centre. In the cation, the two benzene rings are nearly perpendicular to each other, making a dihedral angle of 87.41 (10)°. The cation is linked to the anion by a bifurcated N-H⋯O hydrogen bond. Classical O-H⋯O and weak C-H⋯F hydrogen bonding is also present in the crystal structure. Three C atoms of the N,N-dimethyl-butanaminium moiety are disordered over two sites with refined site occupancies of 0.466 (14) and 0.534 (14).
authors.affiliation: Hainan Provincial Key Laboratory of Tropical Pharmaceutical Herb Chemistry, School of Chemistry and Chemical Engineering, Hainan Normal University, Haikou 571158, People's Republic of China.
authors.forename: En-Ju
authors.initials: EJ
authors.lastname: Wang
authors.forename: Guang-Ying
authors.initials: GY
authors.lastname: Chen