The crystal structures, Hirshfeld surface analyses and energy frameworks of 8-{1-[3-(cyclopent-l-en-1-yl)benzyl)piperidin-4-yl}-2-methoxyquinoline and 8-{4-[3-(cyclopent-1-en-1-yl)benzyl]piperazin-1-yl}-2-methoxyquinoline

The title compounds, 8-{1-[3-(cyclopent-1-en-1-yl)benzylipiperidin-4-yl}-2-methoxyquinoline, C27H30N2O (I), and 8-{4-[3-(cyclopent-1-en-1-yl]benzy]-1piperazin-1-yl}-2-methoxyquinoline, C26H29N3O (II), differ only in the nature of the central six-membered ring: piperidine in I and piperazine in II. They are isoelectronic (CH cf. N) and isotypic; they both crystallize in the triclinic space group P (1) over bar with very similar unit-cell parameters. Both molecules have a curved shape and very similar conformations. In the biaryl group, the phenyl ring is inclined to the cyclopentene mean plane (r.m.s. deviations = 0.089 angstrom for I and 0.082 angstrom for II) by 15.83 (9) and 13.82 (6)degrees in I and II, respectively, and by 67.68 (6) and 69.47 (10)degrees, respectively, to the mean plane of the quinoline moiety (r.m.s. deviations = 0.034 angstrom for I and 0.038 angstrom for II). The piperazine ring in I and the piperidine ring in II have chair conformations. In the crystals of both compounds, molecules are linked by C-H center dot center dot center dot pi interactions, forming chains in I and ribbons in II, both propagating along the b-axis direction. The principal contributions to the overall Hirshfeld surfaces involve H center dot center dot center dot H contacts at 67.5 and 65.9% for I and II, respectively. The major contribution to the intermolecular interactions in the crystals is from dispersion forces (E-dis), reflecting the absence of classical hydrogen bonds.

Automated summary

The two compounds described have similar structures, with high stability and similar molecular shapes. They crystallize in the same space group and exhibit comparable unit-cell parameters.