K. Shakuntala

N-(2,6-Dimethylphenyl)maleamic acid

The asymmetric unit of the title compound, C12H13NO3, contains two independent molecules. The conformation of the N—H bond and the C=O bond in the amide segment are anti to each other. The molecular conformation of each molecule is stabilized by an intramolecular O—H⋯O hydrogen bond. In the crystal, molecules are connected through intermolecular N—H⋯O hydrogen bonds. In addition, there is a carbonyl–carbonyl dipolar interaction with an O⋯C contact of 2.926u2005(3)u2005Å.

N-(3,4-Dichlorophenyl)maleamic acid

The asymmetric unit of the title compound, C10H7Cl2NO3, contains two independent molecules. The molecular conformation of each maleamic unit is stabilized by an intramolecular O—H⋯Ocarbonyl hydrogen bond owing to the anti disposition of the participating entities. The mean planes through the benzene ring and the amido group are inclined at angles of 45.7u2005(1) and 40.8u2005(1)° in the two molecules. In the crystal, the independent molecules self-associate via N—H⋯O hydrogen bonds into zigzag ribbons propagating along the a axis. The ribbons are weakly coupled by C—H⋯π and C—H⋯O interactions.

4-Chloro-N-(2,3-dimethylphenyl)benzenesulfonamide

In the title compound, C14H14ClNO2S, the two aromatic rings are tilted relative to each other by 34.7u2005(1)°. In the crystal, the molecules form zigzag chains along the c axis via intermolecular N—H⋯O hydrogen bonds.

4-Chloro-N-(2,6-dimethylphenyl)benzenesulfonamide

In the title compound, C14H14ClNO2S, the amido H atom orients itself away from both the ortho-methyl groups in the adjacent aromatic ring. The molecule is twisted at the S atom with an C—SO2—NH—C torsion angle of −69.9u2005(2)°. The two aromatic rings are tilted relative to each other by 31.9u2005(1)°. In the crystal, the molecules are packed into zigzag chains along the b axis via intermolecular N—H⋯O hydrogen bonds.

4-Chloro-N-(2-chlorophenyl)benzenesulfonamide

In the crystal structure of the title compound, C12H9Cl2NO2S, the N—C bond in the C—SO2—NH—C segment has gauche torsions with respect to the S=O bonds. The molecule is twisted at the S atom with an C—SO2—NH—C torsion angle of 57.6u2005(3)°. The N—H bond is syn to the ortho-chloro group in the anilino benzene ring. The two benzene rings are tilted relative to each other by 84.7u2005(1)°. The crystal structure features inversion dimers linked by N—H⋯O(S) hydrogen bonds. An intramolecular N—H⋯Cl hydrogen bond is also observed.

Sodium 4,N-dichlorobenzenesulfonamidate sesquihydrate

The structure of the title compound, Na+.C6H4Cl2NO2S−·1.5H2O, resembles the structures of the sodium salts of N-chloroxadbenzenexadsulfonamide, N-chloro-4-methylxadbenzenexadsulfonamide and N-chloro-2-methyl-4-chloroxadbenzenexadsulfonamide. There are two formula units per asymmetric unit. There is no interxadaction between N and Na, and the Na+ cation is attached to three O atoms from water molecules and three sulfonyl O atoms of three different 4,N-dichlorobenzenesulfonamide anions. There are several hydrogen bonds. The S—N distances of 1.584u2005(5) and 1.590u2005(5)u2005A are consistent with an S=N double bond.

4-Chloro-N-(2,3-dimethylphenyl)-2-methylbenzenesulfonamide

The asymmetric unit of the title compound, C15H16ClNO2S, contains two independent moleules. The conformation of the N—H bonds are anti to the ortho-methyl groups in the sulfonyl benzene rings of both the molecules, while the N—H bonds are anti to the ortho- and meta-methyl groups in the aniline ring of one of the molecules and syn in the other. Furthermore, the torsion angles of the C—SO2—NH—C segments in the two molecules of are −66.8u2005(3) and 70.3u2005(3)°. The sulfonyl and the aniline benzene rings are oriented at angles of 44.1u2005(1) and 39.7u2005(1)° in the two molecules. In the crystal, pairs of N—H⋯O hydrogen bonds link the molecules into dimers.

PotassiumN-bromo-2-chlorobenzenesulfonamidate sesquihydrate

In the structure of the title compound, K+·C6H4BrClNO2S−·1.5H2O, the K+ ion is heptacoordinated by three O atoms from water molecules and by four sulfonyl O atoms of N-bromo-2-chlorobenzenesulfonamidate anions. The S—N distance of 1.582u2005(4)u2005Å is consistent with an S=N double bond. The crystal structure is stabilized by intermolecular O—H⋯Br and O—H⋯N hydrogen bonds. The asymmetric unit consits of one potassium cation, one N-bromo-2-chlorobenzenesulfonamidate anion and one water molecule in general positions and one water molecule located on a twofold rotation axis.

4-Chloro-N-(2,3-dichlorophenyl)-2-methylbenzenesulfonamide

The torsion angle of the C—SO2—NH—C moiety in the title compound, C13H10Cl3NO2S, is 50.4u2005(2)°. The sulfonyl and aniline benzene rings are tilted relative to each other by 69.6u2005(1)°. The crystal structure is stabilized by N—H⋯O hydrogen bonds, linking the molecules into zigzag chains parallel to the b axis.

4-Chloro-N-(2,5-dimethylphenyl)benzenesulfonamide

The title compound, C14H14ClNO2S, contains two molecules in the asymmetric unit with different conformations. The C—SO2—NH—C torsion angles are 65.3u2005(2) and 54.6u2005(2)° and the aromatic rings are tilted relative to each other by 59.3u2005(1) and 45.8u2005(1)° in the two molecules. In the crystal, inversion symmetry results in dimers linked by pairs of N—H⋯O hydrogen bonds for both molecules.