N-(3-Methoxybenzoyl)-2-methylbenzenesulfonamide

In the title compound, C15H15NO4S, the dihedral angle between the methyl- and methoxy-substituted benzene rings is 88.99 (12)°. An intramolecular C—H⋯O hydrogen bond occurs. 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 C—H⋯O interactions that form C(8) chains parallel to (001). Molecules are also connected through other C—H⋯O hydrogen bonds along the b axis, forming additional C(8) chains. Two aromatic π–π stacking interactions [centroid–centroid separations = 3.6150 (1) and 3.6837 (1) Å] generate a three-dimensional architecture.


Comment
As a part of our continued efforts to study the crystal structures of N-(aroyl)-arylsulfonamides (Suchetan et al., , 2011, we report herein the crystal structure of the title compound (I).
In the title compound, C 15 H 15 NO 4 S, the dihedral angle between the benzene rings is 88.99°. In the molecule, the conformation between the N-H bond and the ortho-methyl group in the sulfonyl benzene ring is syn. This is similar to what is observed in N-(benzoyl)-2-methylbenzenesulfonamide (II, Suchetan et al., 2010), N-(3-chlorobenzoyl)-2-methylbenzenesulfonamide (III, Suchetan et al., 2011) and N-(3-methylbenzoyl)-2-methylbenzenesulfonamide (IV, . Similarly, the conformation between the N-H bond and the meta-methoxy group in the benzoyl ring is syn, also similar to the conformation in III (Suchetan et al., 2011) and IV .

Experimental
The title compound was prepared by refluxing a mixture of 3-methoxybenzoic acid, 2-methylbenzenesulfonamide and phosphorus 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 (423 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 times of the U eq of the parent atom).

Figure 4
Stacking of molecules through Cg···Cg interactions. Cg1 and Cg2 are the centroids of the carbonyl and sulfonyl bounded benzene rings respectively.

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.