2,4-Dimethyl-N-(4-methylphenyl)benzenesulfonamide

The asymmetric unit of the crystal of the title compound, C15H17NO2S, contains two independent molecules, which are twisted at the S—N bonds with C—SO2—NH—C torsion angles of 48.3 (2) (molecule 1) and −75.7 (3)° (molecule 2). The dihedral angles between the benzene rings are 72.0 (1) (molecule 1) and 78.3 (1)° (molecule 2). The crystal structure features inversion dimers linked by pairs of N—H⋯O hydrogen bonds.

The asymmetric unit of the crystal of the title compound, C 15 H 17 NO 2 S, contains two independent molecules, which are twisted at the S-N bonds with C-SO 2 -NH-C torsion angles of 48.3 (2) (molecule 1) and À75.7 (3) (molecule 2). The dihedral angles between the benzene rings are 72.0 (1) (molecule 1) and 78.3 (1) (molecule 2). The crystal structure features inversion dimers linked by pairs of N-HÁ Á ÁO hydrogen bonds.
The other bond parameters in (I) are similar to those observed in (II), (III), (IV) and other aryl sulfonamides (Perlovich et al., 2006;Gelbrich et al., 2007). The crystal packing of molecules in (I) via N-H···O(S) hydrogen bonds (Table 1) is shown in Fig.2.

Experimental
The solution of 1,3-xylene (1,3-dimethylbenzene) (10 ml) in chloroform (40 ml) was treated dropwise with chlorosulfonic acid (25 ml) at 0° C. After the initial evolution of hydrogen chloride subsided, the reaction mixture was brought to room temperature and poured into crushed ice in a beaker. The chloroform layer was separated, washed with cold water and allowed to evaporate slowly. The residual 2,4-dimethylbenzenesulfonylchloride was treated with p-toluidine in the stoichiometric ratio and boiled for ten minutes. The reaction mixture was then cooled to room temperature and added to ice cold water (100 ml).
The resultant solid 2,4-dimethyl-N-(4-methylphenyl)benzenesulfonamide was filtered under suction and washed thoroughly with cold water. It was then recrystallized to constant melting point from dilute ethanol. The purity of the compound was checked and characterized by recording its infrared and NMR spectra (Savitha & Gowda, 2006).
The prism like colourless single crystals used in x-ray diffraction studies were grown in ethanolic solution by a slow evaporation at room temperature.

Refinement
The H atoms of the NH groups were located in a difference map and later restrained to N-H = 0.86 (1) Å. The other H atoms were positioned with idealized geometry using a riding model with C-H = 0.93-0.96 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the U eq of the parent atom). Fig. 1. Molecular structure of (I), showing the atom labeling scheme and displacement ellipsoids are drawn at the 50% probability level.

Data collection
Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector 5282 independent reflections