2-Chloro-N-(3-methoxybenzoyl)benzenesulfonamide

In the title compound, C14H12ClNO4S, the dihedral angle between the chloro- and methoxy-substituted benzene rings is 87.40 (1)°. In the crystal, adjacent molecules form inversion-related dimers through strong N—H⋯O hydrogen bonds, generating R 2 2(8) loops. The dimers are further connected through two C—H⋯O interactions that form C(11) chains and R 2 2(14) loops. Aromatic π–π stacking interactions [centroid–centroid separation = 3.8574 (1) Å] are also observed.

PAS thanks the University Grants Commission (UGC), India, for financial support under its Minor Research Project scheme.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HG5328).

Sreenivasa Comment
As a part of the efforts to study the crystal structures of N-(aroyl)-arylsulfonamides (Gowda et al., 2010), the crystal structure of the title compound (I) was determined.
In the molecule, the conformation between the N-H bond and the ortho-chloro group in the sulfonyl bound benzene ring is syn. This is similar to that observed in N-(benzoyl)-2-chlorobenzenesulfonamide (II, Gowda et al. 2010).

Experimental
The title compound was prepared by refluxing a mixture of 3-methoxybenzoic acid, 2-chlorobenzenesulfonamide and phosphorous oxychloride (POCl 3 ) for 2 h on a water bath. The resultant mixture was cooled and poured into ice cold water. The solid obtained was filtered and 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 filtered and dried solid was recrystallized to the constant melting point (443 K).
Colorless prisms of (I) were obtained from a slow evaporation of its ethanolic solution at room temperature.

Refinement
The H atom of the NH group was located in a difference map and later refined freely. 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 or 1.5 times of the U eq of the parent atom).

Figure 4
Stacking of molecules through Cg···Cg interactions. Cg is the centroid of the methoxy substituted benzene ring. Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 > 2σ(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.