Three-dimensional hydrogen-bonded framework structures in flunarizinium nicotinate and flunarizinediium bis(4-toluenesulfonate) dihydrate

The structures of two salts of flunarizine, namely 1-bis[(4-fluorophenyl) methyl]-4-[(2E)-3-phenylprop-2-en-1-yl] piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4-bis[(4-fluorophenyl)methyl]-1-[(2E)-3-phenylprop-2-en-1-yl] piperazin-1-ium pyridine-3-carboxylate}, C26H27F2N2+center dot C6H4NO2-, (I), the two ionic components are linked by a short charge-assisted N-H center dot center dot center dot O hydrogen bond. The ion pairs are linked into a three-dimensional framework structure by three independent C-H center dot center dot center dot O hydrogen bonds, augmented by C-H center dot center dot center dot pi(arene) hydrogen bonds and an aromatic pi-pi stacking interaction. In flunarizinediium bis(4-toluenesulfonate) dihydrate {systematic name: 1-[bis(4-fluorophenyl) methyl]-4-[(2E)-3-phenylprop-2-en- 1-yl] piperazine-1,4-diium bis(4-methylbenzenesulfonate) dihydrate}, C26H28F2N22+center dot 2C(7)H(7)O(3)S(-)center dot 2H(2)O, (II), one of the anions is disordered over two sites with occupancies of 0.832 (6) and 0.168 (6). The five independent components are linked into ribbons by two independent N-H center dot center dot center dot O hydrogen bonds and four independent O-H center dot center dot center dot O hydrogen bonds, and these ribbons are linked to form a three-dimensional framework by two independent C-H center dot center dot center dot O hydrogen bonds, but C-H center dot center dot center dot pi(arene) hydrogen bonds and aromatic pi-pi stacking interactions are absent from the structure of (II). Comparisons are made with some related structures.