N-[4-(Ethylsulfamoyl)phenyl]acetamide

The title compound, C10H14N2O3S, crystallized with two molecules (A and B) in the asymmetric unit. The terminal methyl group of the ethylsulfonamide moiety in molecule B is disordered over two sets of sites with an occupancy ratio of 0.61 (1):0.39 (1). Both molecules have L-shaped conformations. In molecule A, the dihedral angles between the benzene ring and its ethylsulfonamide and methylamide substituents are 83.5 (3) and 13.34 (18)°, respectively. Equivalent values for molecule B are 87.9 (3) and 6.32 (16)°, respectively. The C—S—N—C torsion angles are 66.5 (3)° for A and −64.4 (3)° for B, indicating similar twists about the S—N bonds, but in opposite senses. In the crystal, the A molecules are linked by pairs of Ns—H⋯O (s = sulfonamide) hydrogen bonds, generating inversion dimers containing R 2 2(8) rings, while the B molecules are linked by Ns—H⋯O hydrogen bonds into C(10) [100] chains. Finally, Na—H⋯O (a = amide) hydrogen bonds link the A-molecule dimers and B-molecule chains into a three-dimensional network.

The title compound, C 10 H 14 N 2 O 3 S, crystallized with two molecules (A and B) in the asymmetric unit. The terminal methyl group of the ethylsulfonamide moiety in molecule B is disordered over two sets of sites with an occupancy ratio of 0.61 (1):0.39 (1). Both molecules have L-shaped conformations. In molecule A, the dihedral angles between the benzene ring and its ethylsulfonamide and methylamide substituents are 83.5 (3) and 13.34 (18) , respectively. Equivalent values for molecule B are 87.9 (3) and 6.32 (16) , respectively. The C-S-N-C torsion angles are 66.5 (3) for A and À64.4 (3) for B, indicating similar twists about the S-N bonds, but in opposite senses. In the crystal, the A molecules are linked by pairs of N s -HÁ Á ÁO (s = sulfonamide) hydrogen bonds, generating inversion dimers containing R 2 2 (8) rings, while the B molecules are linked by N s -HÁ Á ÁO hydrogen bonds into C(10) [100] chains. Finally, N a -HÁ Á ÁO (a = amide) hydrogen bonds link the A-molecule dimers and B-molecule chains into a three-dimensional network.   Table 1 Hydrogen-bond geometry (Å , ).
IUK thanks the Higher Education Commission of Pakistan for financial support under the project to strengthen the Materials Chemistry Laboratory at GCUL.
The title compound, C 10 H 14 N 2 O 3 S, crystallized with two molecules (A and B) in the asymmetric unit (Fig. 1). The -CH 3 group of the ethylsulfonamide moiety (atom C20) in molecule B is disordered over two positions [C20a and C20b with occupancies 0.61 (1):0.39 (1)]. Both molecules have L-shaped conformations in which the ethylsulfonamide group is roughly perpendicular to the benzene ring, but the methyl-amide group is almost coplanar with the same ring. In molecule A the dihedral angles between the benzene ring (C1-C6) and the ethylsulfonamide (S1,N1,C9,C10) and methylamide (N2,C7,O3,C8) moieties are 83.5 (3) and 13.34 (18) In the crystal, the A molecules are linked by pairs of N s -H···O (s = sulfonamide) hydrogen bonds to generate inversion dimers containing R 2 2 (8) rings (Fig. 2), while the B molecules are linked by N s -H···O hydrogen bonds into C(10) [100] chains (Fig. 3). Finally, N a -H···O (a = amide) hydrogen bonds link the dimers and chains into a three-dimensional network -see Table 1 for details of the hydrogen bonding.

Experimental
Ethyl amine (1 mmol, 0.0654 ml) was dissolved in distilled water (20 ml) in a round bottom flask (100 ml) and 4-(acetylamino)benzenesulfonyl chloride (1 mmol, 0.23367 g) was added with stirring at room temperature while keeping the pH of solution between 8.0-9.0 with sodium carbonate solution (3%). After 4 h, the white precipitate formed was filtered, washed with distilled water and dried. Colourless block-like crystals of the title compound were grown from methanol by slow evaporation.

Refinement
Atom C20 and its attached H atoms were modelled as being disordered over two sets of sites with occupancies 0.61 (1):0.39 (1). The N-bound H atoms were located in difference Fourier maps and their positions were freely refined with the constraint U iso (H) = 1.2U eq (N) applied. The C-bound hydrogen atoms were placed in calculated positions (C-H = 0.93-0.97 Å) and refined as riding atoms with U iso (H) = k × U eq (C), where k = 1.5 for methyl H-atoms and k = 1.2 for all supplementary materials sup-2 other H-atoms. The methyl groups were allowed to rotate, but not to tip, to best fit the electron density. The methyl H-atoms attached to C8 and C18 were modelled as being equally disordered over two sets of sites, with occupancies 0.5:0.5. Fig. 1. The molecular structure of the two independent molecules (A and B) of the title compound, showing the numbering scheme and 50% displacement ellipsoids. Only the major disordered component (C20A) for atom C20 is shown. The disordered methyl H-atom sites for C8 and C18 are shown in black and orange.

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 > 2sigma(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Occ. (