The structures of eleven (4-phenyl)piperazinium salts containing organic anions.

Eleven (4-phenyl)piperazinium salts containing organic anions have been prepared and structurally characterized, namely, 4-phenylpiperazin-1-ium f4l-uorobenzoate monohydrate, C10H15N₂+-C₇H₄FO₂-H₂O, 1; 4-phenylpiperazin-1-ium 4-bromobenzoate monohydrate, C₁₀H₁₅N₂+-C₇H₄NO₂-H₂O, 3; 4-phenylpiperazin-1-ium 4-iodobenzoate, C10H15N₂+-C₇H₄IO2_, 4; 4-phenylpiperazin-1-ium 4-nitrobenzoate, C10H15N₂+-C₇H₄NO₄_, 5; 4-phenylpiperazin-1-ium 3,5-dinitrosalicylate, C10H15N₂+-C₇H₃N₂O7_, 6; 4-phenylpiperazin-1-ium 3d,i5n-itrobenzoate, C10H15N₂+-C₇H₃N₂O6_, 7; 4-phenylpiperazin-1-ium picrate, C10H15N₂+-C₆H₂N₃O7_, 8; 4-phenylpiperazin-1-ium benzoate monohydrate, C10H15N₂+-C₇H5O2_-H₂O, 9; 4-phenylpiperazin-1-ium p-toluenesulfonate, C10H15N₂+-C₇H7O₃S_, 10; 4-phenylpiperazin-1-ium tartarate monohydrate, C10H15N₂+-C4H5O6~-H₂O, 11; and 4-phenylpiperazin-1-ium fumarate, C10H15N₂+-C4H₃O₄_, 12. Compounds 1 and 3-12 are all 1:1 salts with the acid proton transferred to the phenylpiperaizine basic N atom (the secondary amine) with the exception of 3 where there is disorder in the proton position with it being 68% attached to the base and 32% attached to the acid. Of the structures with similar stoichiometries only 3 and 9 are isomorphous. The 4-phenyl substituent in all cases occupies an equatorial position except for 12 where it is in an axial position. The crystal chosen for structure 7 was refined as a nonmerohedral twin. There is disorder in 5, 6, 10 and 11. For both 5 and 6, a nitro group is disordered and was modeled with two equivalent orientations with occupancies of 0.62 (3)/0.38 (3) and 0.690 (11)/0.310 (11), respectively. For 6,10 and 11, this disorder is associated with the phenyl ring of the phenylpiperazinium cation with occupancies of 0.687 (10)/0.313 (10), 0.51 (7)/0.49 (7) and 0.611 (13)/389 (13), respectively. For all salts, the packing is dominated by the N--H--O hydrogen bonds formed by the cation and anion. In addition, several structures contain C--H--Ä (1, 3, 4, 8, 9,10, and 12) and aromatic ä-ä stacking interactions (6 and 8) and one structure (5) contains a -NO2"-x interaction. For all structures, the Hirshfeld surface fingerprint plots show the expected prominent spikes as a result of the N--H--O and O--H--O hydrogen bonds. [ABSTRACT FROM AUTHOR]