B. S. Palakshamurthy

Crystal structure of 1-tosyl-1,2,3,4-tetra-hydro-quinoline.

In the title compound, C16H17NO2S, the heterocyclic ring adopts a half-chair conformation and the bond-angle sum at the N atom is 350.2°. The dihedral angle between the planes of the aromatic rings is 47.74 (10)°. In the crystal, molecules are linked by C—H⋯O hydrogen bonds to generate [010] chains.

4-Meth-oxy-N-[(4-methyl-phen-yl)sulfon-yl]benzamide including an unknown solvate.

In the title compound, C15H15NO4S, the dihedral angle between the benzene rings is 78.62 (16)°. In the crystal, adjacent molecules are linked along the c axis into C(4) chains through strong N—H⋯O hydrogen bonds. Molecules are further connected through C—H⋯O hydrogen bonds into a hexameric unit generating an R 6 6(66) motif. Another C—H⋯O interaction connects the molecules along the c axis, forming C(5) chains. A region of disordered electron density, most probably disordered methanol–water solvent molecules, was treated 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 this disordered solvent.

2-Chloro-N-(4-methoxybenzoyl)benzene-sulfonamide

In the title compound, C14H12ClNO4S, the dihedral angle between the aromatic rings is 82.07 (1)° and the dihedral angle between the planes defined by the S—N—C=O fragment and the sulfonyl benzene ring is 82.46 (3)°. In the crystal, the molecules are linked into C(4) chains running along [001] by strong N—H⋯O hydrogen bonds. A C—H⋯O interaction reinforces the [001] chains: its graph-set symbol is C(7). The chains are cross-linked into (100) sheets by further C—H⋯O interactions as C(6) chains along [001]. The structure also features weak π–π stacking interactions [centroid–centroid distances = 3.577 (1) and 3.8016 (1) Å].

4'-Cyano-biphenyl-4-yl 7-diethyl-amino-2-oxo-2H-chromene-3-carboxyl-ate.

In the title compound, C27H22N2O4, the dihedral angles between the central benzene ring and the cyanobenzene ring and the 2H-coumarin ring system (r.m.s. deviation = 0.014 Å) are 22.95 (11) and 75.59 (8)°, respectively. Both terminal C atoms of the pendant diethylamino group lie to the same side of the coumarin ring system [deviations = 1.366 (2) and 1.266 (2) Å]. In the crystal, molecules are linked by C—H⋯O and C—H⋯N hydrogen bonds and a C—H⋯π interaction, generating a three-dimensional network.

Ethyl (2E)-2-cyano-3-(4-meth­oxy­phen­yl)acrylate

In the title compound, C13H13NO3, the conformation across the C=C bond is synperiplanar, the torsion angle of the segment C(ring)—C=C—C(N) being 3.2 (5)°. In the crystal, molecules are linked into inversion dimers, arranged in a zigzag pattern, through two C—H⋯O interactions generating R 2 2(10) and R 2 2(14) motifs. These dimers are arranged in a zigzag pattern in the crystal structure. The molecules are further linked along the c axis through weak C—H⋯π interactions, and weak π⋯π interactions [centroid–centroid separation = 3.9986 (17) Å] are also observed.

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

In the crystal structure of the title compound, C19H21F3N2O2S, the piperazine ring adopts a chair conformation. The dihedral angles between the mean plane of the piperazine ring and the tosyl and trifluoromethylphenyl 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 interactions.

Crystal structure of 4-methoxyphenyl 2-oxo-2H-chromene-3-carboxylate

In the title compound, C17H12O5, the dihedral angle between the planes of the coumarin ring system (r.m.s. deviation = 0.015 Å) and the benzene ring is 48.04 (10)°. The central CO2 group subtends a dihedral angle of 27.15 (11)° with the coumarin ring system and 74.86 (13)° with the benzene ring. In the crystal, molecules are linked by C—H⋯O interactions, which generate a three-dimensional network. Very weak C—H⋯π interactions are also observed.

Crystal structure of 1-benzylsulfonyl-1,2,3,4-tetrahydroquinoline

In the title compound, C16H17NO2S, the heterocyclic ring adopts a half-chair conformation and the bond-angle sum at the N atom is 354.6°. The dihedral angle between the planes of the aromatic rings is 74.15 (10)°. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds, generating C(8) and C(4) chains propagating along [100] and [010], respectively, which together generate (001) sheets.

3,4-Di­fluoro-2-hy­droxy­benzoic acid

In the title compound, C7H4F2O3, an intramolecular O—H⋯O hydrogen bond is observed. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds generate R 2 2(8) ring motifs. These dimers are linked by C—H⋯O and C—H⋯F hydrogen bonds, forming sheets lying parallel to (30-1). The sheets are linked by aromatic π–π stacking interactions [inter-centroid distance = 3.7817 (9) Å], forming a three-dimensional structure.

N-Ethyl-2,2-dimethyl-N-(3-methyl­phen­yl)propanamide

In the title compound, C14H21NO, the conformation across the N—C(O) bond is syn-periplanar, the C—N—C—C torsion being −5.9 (5)°. The atoms of the ethyl group attached to the N atom are disordered over two sets of sites with occupancy ratios of 0.65 (2):0.35 (2) (CH2) and 0.689 (14):0.311 (14) (CH3)are linked by very weak C—H⋯O interactions forming C(8) chains along [001]. C—H⋯π interactions link the molecules along the c-axis direction.