N-(4-Chlorophenyl)-N′-(3-methylphenyl)succinamide monohydrate

In the title hydrate, C17H17ClN2O2·H2O, the dihedral angles formed by the aromatic rings of the chlorobenzene and methylbenzene groups with the mean planes of their attached NH—C(O)—CH2 fragments are 16.6 (2) and 22.8 (2)°, respectively. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the components into a two-dimensional network parallel to the ab plane.

BSS thanks the University Grants Commission, Government of India, New Delhi, for the award of a research fellowship under its faculty improvement program.

Comment
The amide and sulfonamide moieties are important constituents of many biologically important compounds. As part of our studies on the effects of substitutions on the structures and other aspects of N-(aryl)-amides (Arjunan et al., 2004;Gowda et al., 2000;Saraswathi et al., 2011); N-(aryl)-methanesulfonamides (Gowda et al., 2007) and on N-chloro-arylsulfonamides (Gowda & Kumar, 2003), in the present work, the structure of N-(4-Chlorophenyl),N-(3-methylphenyl)-succinamide monohydrate has been determined ( Fig.1). In the C-NH-C ( Further, conformations of the N-H bond in the amide fragment is anti to the meta-methyl group in the adjacent benzene ring, similar to that observed in (II). Further, the dihedral angle between the 4-chlorophenyl ring and the adjacent NH-C(O)-CH 2 segment is 16.6 (2)° and that between the 3-methylphenyl ring and the adjacent NH-C(O)-CH 2 segment is 22.8 (2)°.

Experimental
Succinic anhydride (0.01 mol) in toluene (25 ml) was treated drop wise with m-toluidine (0.01 mol) also in toluene (20 ml) with constant stirring. The resulting mixture was stirred for one hour and set aside for an additional hour at room temperature for completion of the reaction. The mixture was then treated with dilute hydrochloric acid to remove unreacted m-toluidine.
The resultant solid N-(3-methylphenyl)-succinamic acid was filtered under suction and washed thoroughly with water to remove the unreacted succinic anhydride and succinic acid. The compound was recrystallized to constant melting point from ethanol. The purity of the compound was checked and characterized by its infrared and NMR spectra.
The N-(3-methylphenyl)-succinamic acid obtained was then treated with phosphorous oxychloride and excess of 4chloroaniline at room temperature with constant stirring. The resultant mixture was stirred for 4 h, kept aside for additional 6 h for completion of the reaction and poured slowly into crushed ice with constant stirring. It was kept aside for a day.
The resultant solid, N-(4-Chlorophenyl), N-(3-methylphenyl)-succinamide monohydrate was filtered under suction, washed thoroughly with water, dilute sodium hydroxide solution and finally with water. It was recrystallized to constant melting point from a mixture of acetone and chloroform. The purity of the compound was checked and characterized by its infrared and NMR spectra.
Prism like colorless single crystals used in the X-ray diffraction studies were grown in 1:1 mixture of acetone and chloroform at room temperature. All H atoms were refined with isotropic displacement parameters. The U iso (H) values were set at 1.2U eq (C-aromatic, N) and 1.5U eq (C-methyl).
Figures Fig. 1. The asymmetric unit of the title compound with displacement ellipsoids drawn at the 50% probability level. The intermolecular O-H···O hydrogen bond involving the water molecule is drawn as a dashed line.