1-(3,4-Di-fluoro-benz-yl)-4-(4-methyl-phenyl-sulfon-yl)piperazine.

In the title compound, C18H20F2N2O2S, the central piperazine ring adopts a chair conformation. The dihedral angle between the two benzene rings is 40.20°, whereas those between the piperazine ring (considering the best fit plane through all the non-H atoms) and the sulfonyl-bound benzene and di-fluoro-benzene rings are 74.96 and 86.16°, respectively. In the crystal, mol-ecules are stacked along the a axis through weak C-H⋯O and C-H⋯F inter-actions.

An unknown solvate of 1-(2,4-di-chloro-benz-yl)-4-[(4-methyl-phen-yl)sulfon-yl]piperazine.

In the title compound, C18H20Cl2N2O2S, the piperazine ring adopts a chair conformation. The dihedral angle between the sulfonyl-bound benzene ring and the best-fit plane through the six non-H atoms of the piperazine ring is 72.22 (12)°; those between the di-chloro-benzene ring and the sulfonyl and piperazine rings are 2.44 (13) and 74.16 (2)°, respectively. In the crystal, mol-ecules are connected through weak C-H⋯O inter-actions into a hexa-meric unit generating a R 6 (6)(60) motif in the ab plane. The mol-ecules are also connected into C(4) chains through weak C-H⋯N inter-actions. The solvent used to grow the crystal was a mixture of di-chloro-methane and methanol, but the resulting electron density was uninter-pretable. The solvent contribution to the scattering was removed with the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. The formula mass and unit-cell characteristics do not take into account the disordered solvent.

1-Tosyl-4-[2-(trifluoro-meth-yl)benz-yl]piperazine.

In the crystal structure of the title compound, C(19)H(21)F(3)N(2)O(2)S, the piperazine ring adopts a chair conformation. The dihedral angles between the mean plane of the piperazine ring and the tosyl and trifluoro-methyl-phenyl rings are 74.52 (3) and 68.30 (2)°, respectively. The sulfonamide N atom deviates from the plane defined by the three attached atoms by 0.327 (1) Å. The crystal structure is stabilized by weak C-H⋯π inter-actions.