Synthesis, Characterization and Crystal Structure of 1-(2-benzamidophenyl)-3-benzoylthiourea Hemihydrate

The dissymmetric compound C21H17N3O2S.0.5H2O obtained by a reaction of 1,2-diaminobenzene, potassium thiocyanate and benzoyl chloride in 1/1/2 ratio is characterized by elemental analyses, IR, and NMR spectroscopies. The structure is elucidated by X-ray diffraction technic. The compound crystallizes in the monoclinic system with a space group of I2. The asymmetric unit contains one hemihydrate organic molecule. The title thiourea derivative, features an almost planar, C2N2S (S1/N1/N2/C7/C8) moiety, with a maximum deviation from the least-squares plane of 0.0422 (3) A. This moiety is flanked by a disubstituted and a monosubstituted phenyl rings. The dihedral angles between the thiourea and the monosubstituted phenyl ring and the thiourea and the central disubstituted phenyl ring are respectively 10.418 (7)° and 60.292 (2)°, indicating twist in the molecule. On the other arm, a phenyl ring supported by an amide function, which is linked to the central ring through the nitrogen atom, is present. The dihedral angle between this phenyl group and the central disubstituted phenyl is 76.862 (7)° showing that their mean planes are not coplanar. Intramolecular S(thiono)—H…O(water) hydrogen bonds which close in S (6) and S (7) rings consolidate the conformation. Intermolecular N(amido)—H…O(carbonyl) which form layers parallel to the ac plane stabilized the structure.