P. Nithya

Environmentally benign one-pot synthesis and antimicrobial activity of 1-methyl-2,6-diarylpiperidin-4-ones

An efficient and environmentally benign one-pot method for the synthesis of 1-methyl-2,6-diarylpiperidin-4-ones using montmorillonite K-10 as a catalyst has been developed. Antimicrobial activity of the compounds has been tested against selected representatives of Gram-positive and Gram-negative bacteria and fungi.

1-(3-Phenyl­isoquinolin-1-yl)hydrazine

The title compound, C15H13N3, contains two independent molecules in the asymmetric unit. The isoquinoline moiety and phenyl rings form dihedral angles of 4.38 (2) and 10.14 (3)° in the two independent molecules. The crystal packing is stabilized by N—H⋯N molecular dimers formed across a center of symmetry.

1,3-Dimethyl-2,6-diphenyl-piperidin-4-one.

In the title moleclue, C19H21NO, the 4-piperidone ring adopts a chair conformation in which the two benzene rings and the methyl group attached to C atoms all have equatorial orientations. In the crystal structure, centrosymmetric dimers are formed through weak intermolecular C—H⋯O hydrogen bonds [the dihedral angle between the aromatic rings is 58.51 (5)°].

1-(4-Chloro-phen-yl)-2-[(3-phenyl-isoquinolin-1-yl)sulfan-yl]ethanone.

The title compound, C23H16ClNOS, exhibits dihedral angles of 11.73 (1) and 66.07 (1)°, respectively, between the mean plane of the isoquinoline system and the attached phenyl ring, and between the isoquinoline system and the chlorophenyl ring. The dihedral angle between the phenyl and chlorophenyl rings is 54.66 (1)°.

3-Phenyl­isoquinolin-1(2H)-one

The title compound, C15H11NO, consists of a planar isoquinolinone group to which a phenyl ring is attached in a twisted fashion [dihedral angle = 39.44 (4)°]. The crystal packing is dominated by intermolecular N—H⋯O and C—H⋯O hydrogen bonds which define centrosymmetric dimeric entitities.

3-(1,3-Dioxolan-2-yl)-2-hydrazino-7-methyl-quinoline.

In the title molecule, C13H15N3O2, the dihedral angle between the mean plane of the 1,3-dioxolane group and the 2-hydrazino-7-methylisoquinoline unit is 85.21 (5)°. The conformation of the molecule is influenced by bifurcated N—H⋯(O,O) and N—H⋯N intramolecular hydrogen bonds. In the crystal structure, molecules are linked via intermolecular N—H⋯O hydrogen bonds, forming extended chains along [001].

1-Benzoyl-3-methyl-2,6-diphenyl-4-piperidone

In the title moleclue, C25H23NO2, the 4-piperidone ring adopts a boat conformation. The molecular conformation is stabilized by an intramolecular C—H⋯O hydrogen bond. In the crystal, molecules are connected through weak intermolecular C—H⋯O hydrogen bonds.

2,6-Bis(3-methoxy­phen­yl)-3-methyl­piperidin-4-one

In the molecule of the title compound, C20H23NO3, the bulky methoxyphenyl substituents at the equatorial 2,6-positions crowd the vicinity of the equatorial amino H atom and prevent it from forming intermolecular hydrogen bonds. The piperidine ring adopts a distorted chair conformation.

1,3,6-Trimethyl­pyrano[4,3-b]pyrrol-4(1H)-one

All the non-H atoms of the title compound, C10H11NO2, are almost coplanar [maximum deviation = 0.040 (3) Å]. The crystal structure is stabilized by C—H⋯O hydrogen bonds.

1-(2-Chloroacetyl)-3-methyl-2,6-diphenylpiperidin-4-one

The asymmetric unit of the title compound, C20H20ClNO2, contains two crystallographically independent molecules of similar geometry. The piperidine ring adopts a distorted boat conformation in both molecules, in which the N atom assumes an almost planar configuration.