Crystal structures of three N-acylhydrazone isomers

Abstract

The crystal structures of three isomers of (E)-4-chloro-N-{2-[2-(chlorobenzylidene)hydrazinyl]-2-oxoethyl}benzenesulfonamide, namely, (E)-4-chloro-N-{2-[2-(2-chlorobenzylidene)hydrazinyl]-2-oxoethyl}benzenesulfonamide (I), (E)-4-chloro-N-{2-[2-(3-chlorobenzylidene)hydrazinyl]-2-oxoethyl}benzenesulfonamide (II) and (E)-4-chloro-N-{2-[2-(4-chlorobenzylidene)hydrazinyl]-2-oxoethyl}benzenesulfonamide (III), with the general formula C15H13Cl2N3O3S are described, with the chloro group in ortho, meta and para positions in the benzylidene benzene ring. All the three isomeric compounds crystallize in the centrosymmetric triclinic P\overline{1} space group with one molecule each in the asymmetric unit and two molecules in the unit cell. The dihedral angles between the two phenyl rings are 11.09 (14), 53.79 (18) and 72.37 (11)° in (I), (II) and (III), respectively. The central part of the molecule (–C—N—N=C–) is almost linear with C—N—N—C torsion angles of 179.1 (2), −169.5 (3) and 178.5 (2)° for (I), (II) and (III), respectively. In all the three crystals, the molecules form inversion dimers with R22(8) ring motifs, which are further augmented by C—H...O interactions.

Keywords

• crystal structure
• n-acylhydrazone
• dihedral angle
• inversion dimers
• c—h...o interaction