N-(3-Methylbenzoyl)-2-nitrobenzenesulfonamide

In the title compound, C14H12N2O5S, the conformation between the N—H group and the ortho-nitro group in the sulfonyl benzene ring is syn and that between the C=O and meta-methyl groups in the benzoyl ring is anti. The molecule is twisted at the S—N bond with a torsion angle of 64.3 (2)°. The dihedral angle between the sulfonyl benzene ring and the —SO2—NH—C—O segment is 75.73 (7)° and that between the sulfonyl and benzoyl benzene rings is 89.5 (1)°. The crystal structure features inversion-related dimers linked by pairs of N—H⋯O(S) hydrogen bonds.

In the title compound, C 14 H 12 N 2 O 5 S, the conformation between the N-H group and the ortho-nitro group in the sulfonyl benzene ring is syn and that between the C O and meta-methyl groups in the benzoyl ring is anti. The molecule is twisted at the S-N bond with a torsion angle of 64.3 (2) . The dihedral angle between the sulfonyl benzene ring and the -SO 2 -NH-C-O segment is 75.73 (7) and that between the sulfonyl and benzoyl benzene rings is 89.5 (1) . The crystal structure features inversion-related dimers linked by pairs of N-HÁ Á ÁO(S) hydrogen bonds.
BTG thanks the University Grants Commission, Government of India, New Delhi, for a special grant under the UGC-BSR one-time grant to faculty.
The conformation between the N-H and C=O bonds in the C-SO 2 -NH-C(O) segment is anti and the N-C bond in the segment has gauche torsion with respect to the S═O bonds ( Fig.1), similar to that observed in N-(2-chlorobenzoyl)-2-nitrobenzenesulfonamide (II) (Suchetan et al., 2012). In (I), the conformation between the N-H bond and the ortho-nitro group in the sulfonyl benzene ring is syn, similar to that observed in (II). Further, the conformation of the C═O is anti to the meta-methyl group in the benzoyl ring, similar to that observed between the C═O and the ortho-Cl atom in (II).
The molecule is twisted at the S-N bond with the torsional angle of 64.32 (20)°, compared to the value of -59.68 (17)°i n (II).
The dihedral angle between the sulfonyl benzene ring and the -SO 2 -NH-C-O segment is 75.7 (1)°, compared to the value of 77.5 (1)° in (II). Furthermore, the dihedral angle between the sulfonyl and the benzoyl benzene rings is 89.5 (1)°, compared to the value of 71.2 (1)° in (II).
In the crystal, the intermolecular N-H···O (S) hydrogen bonds (Table 1) link the molecules into dimeric chains. Part of the crystal structure is shown in Fig. 2.

Experimental
The title compound was prepared by refluxing a mixture of m-methylbenzoic acid (0.02 mole), 2-nitrobenzenesulfonamide (0.02 mole) and excess phosphorous oxychloride for 3 h on a water bath. The resultant mixture was cooled and poured into crushed ice. The solid, N-(3-methylbenzoyl)-2-nitrobenzenesulfonamide, obtained was filtered, washed thoroughly with water and then dissolved in sodium bicarbonate solution. The compound was later reprecipitated by acidifying the filtered solution with dilute HCl. It was filtered, dried and recrystallized.
Prism like colourless single crystals of the title compound used in X-ray diffraction studies were obtained by slow evaporation of its toluene solution at room temperature.

Refinement
The H atom of the NH group was located in a difference map and later restrained to N-H = 0.86 (2) %A. The other H atoms were positioned with idealized geometry using a riding model with the aromatic C-H = 0.93 Å and the methyl C-H = 0.93 Å. All H atoms were refined with isotropic displacement parameters set at 1.2 U eq (C-aromatic, N) and 1.5 U eq (C-methyl). Fig. 1. Molecular structure of the title compound, showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.