N-Benzoyl-2-chlorobenzenesulfonamide

In the crystal structure of the title compound, C13H10ClNO3S, the conformation of the of the N—H bond in the C—SO2—NH—C(O) segment is anti to the C=O bond. The dihedral angle between the two benzene rings is 73.3 (1)°. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds occur.

In the crystal structure of the title compound, C 13 H 10 ClNO 3 S, the conformation of the of the N-H bond in the C-SO 2 -NH-C(O) segment is anti to the C O bond. The dihedral angle between the two benzene rings is 73.3 (1) . In the crystal, inversion dimers linked by pairs of N-HÁ Á ÁO hydrogen bonds occur.   Table 1 Hydrogen-bond geometry (Å , ). (3) 172 (3) Symmetry code: (i) Àx; Ày þ 1; Àz þ 1.

Experimental
The title compound was prepared by refluxing a mixture of benzoic acid (0.02 mole), 2-chlorobenzenesulfonamide (0.02 mole) and excess phosphorous oxy chloride for 3 h on a water bath. The resultant mixture was cooled and poured into crushed ice. The solid, N-(benzoyl)2-chlorobenzenesulfonamide, 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. The compound 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 the distance N-H = 0.85 (1) Å. The other H atoms were positioned with idealized geometry using a riding model with C-H = 0.93 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the U eq of the parent atom).

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
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 Rfactors(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.