N-(2-Methylphenyl)-4-nitrobenzenesulfonamide

In the title compound, C13H12N2O4S, the dihedral angle between the planes of the rings is 51.11 (10)°. In the crystal, molecules are linked into inversion dimers through pairs of N—H⋯O(S) hydrogen bonds.

In the title compound, C 13 H 12 N 2 O 4 S, the dihedral angle between the planes of the rings is 51.11 (10) . In the crystal, molecules are linked into inversion dimers through pairs of N-HÁ Á ÁO(S) hydrogen bonds.
The conformation of the N-C bond in the -SO 2 -NH-C segment has gauche torsion with respect to the S═O bonds ( Fig.1). Further, the conformation of the N-H bond in the -SO 2 -NH-segment is syn to the ortho-methyl group in the anilino ring, compared to syn conformation observed between the N-H bond and ortho-nitro group in the sulfonyl benzene ring in N-(4-methylphenyl)-2-nitrobenzenesulfonamide (I) (Chaithanya et al., 2012). The molecule is twisted at the S-N bond with the torsional angle of -58.97 (21)°, compared to the value of 76.55 (18)° in (I).
The dihedral angle between the sulfonyl and the anilino rings is 51.11 (10)°, compared to the value of 72.64 (8)° in (I).
In the crystal structure, the pairs of intermolecular N-H···O (S) hydrogen bonds (Table 1) link the molecules into inversion dimers. Part of the crystal structure is shown in Fig. 2.

Experimental
The title compound was prepared by treating 4-nitrobenzenesulfonylchloride with 2-methylaniline in the stoichiometric ratio and boiling the reaction mixture for 15 minutes. The reaction mixture was then cooled to room temperature and added to ice cold water (100 ml). The resultant solid N-(2-methylphenyl)-4-nitrobenzenesulfonamide was filtered under suction and washed thoroughly with cold water and dilute HCl to remove the excess sulfonylchloride and aniline, respectively. It was then recrystallized to constant melting point (429 K) from dilute ethanol. The purity of the compound was checked and characterized by its infrared spectra.
Prism like light brown single crystals of the title compound used in X-ray diffraction studies were grown in ethanolic solution by slow evaporation of the solvent at room temperature.

Refinement
H atoms bonded to C were positioned with idealized geometry using a riding model with the aromatic C-H = 0.93 Å, methyl C-H = 0.96 Å. The coordinates of the amino H atom were freely refined with the N-H distance restrained to 0.86 (2) Å. All H atoms were refined with isotropic displacement parameters set at 1.2 U eq (C-aromatic, N) or 1.5 U eq (Cmethyl) of the parent atom. 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figure 1
Molecular structure of the title compound, showing the atom labelling scheme and with displacement ellipsoids drawn at the 50% probability level.  Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.