K. Krishnasamy

2,4-Bis(4-fluoro­phen­yl)-1,5-dimethyl-3-aza­bicyclo­[3.3.1]nonan-9-one

The asymmetric unit of the title compound, C22H23F2NO, contains two independent molecules, A and B. The bicyclic system adopts a twin-chair conformation in both molecules. The dihedral angles between the fluorophenyl rings are 55.27 (8) and 56.37 (7)° in molecules A and B, respectively. The NH groups are not involved in hydrogen bonding due to the steric hindrance of fluorophenyl groups. The crystal structure features weak C—H⋯O interactions.

2,4-Bis(furan-2-yl)-1,5-dimethyl-3-aza-bicyclo-[3.3.1]nonan-9-one.

In the title compound, C18H21NO3, the bicyclic ring system adopts a twin-chair conformation. The two methyl groups attached to the bicycle are in an equatorial orientation for both rings. One of the furan rings is disordered over two orientations with an occupancy ratio of 0.686 (6):0.314 (6). In the crystal, very long N—H⋯O hydrogen bonds connect the molecules into a chain perpendicular to the ac plane.

Crystal structure of 1-cyclo­propane­carbon­yl-3-methyl-2,6-di-p-tolyl­piperidin-4-one

The title compound, C24H27NO2, crystallizes with two independent molecules (A and B) in the asymmetric unit. The two molecules have very similar conformations and each exhibits an intramolecular C—H⋯π interaction. The central piperidine rings adopt boat conformations and the p-tolyl rings are inclined to the mean plane of the piperidine ring by 71.21 (11) and 89.86 (12)° in molecule A and by 68.01 (12) and 89.33 (12)° in molecule B. The cyclopropanecarbonyl group is oriented at an angle of 68.5 (2)° with respect to the mean plane of the piperidine ring in molecule A and 66.2 (2)° in molecule B. In the crystal, the A and B molecules are linked by C—H⋯O hydrogen bonds, enclosing R 2 1(6) ring motifs, forming ribbons running along the a-axis direction.

Crystal structure of methyl 2-[2,4-bis-(4-fluoro-phen-yl)-3-aza-bicyclo-[3.3.1]nonan-9-yl-idene]hydrazine-carboxyl-ate.

In the title compound, the bicyclic ring system adopts a twin-chair conformation. In the crystal, N—H⋯O, C—H⋯O and C—H⋯F interactions connect the molecules, forming supramolecular chains propagating along the b-axis direction.

rac-7-Methyl-3-[(7-methyl-4-oxo­chro­man-3-yl)meth­yl]-4H-chromen-4-one

In the racemic title compound, C21H18O4, the chromone ring is essentially planar [maximum deviation from the least-squares plane = 0.026 (3) Å], with a dihedral angle of 78.18 (12)° between the benzene rings of the chromanone and chromenone moieties. In the crystal, there are weak π–π stacking interactions [minimum ring centroid separation = 3.9286 (17) Å].