Crystal structure and Hirshfeld surface analysis of (E)-N′-[4-(piperidin-1-yl)benzyl­idene]aryl­sulfono­hydrazides

The crystal structures and Hirshfeld surface analyses of three Schiff bases, namely (E)-N′-[4-(piperidin-1-yl)benzyl­idene]benzene­sulfono­hydrazide, C18H21N3O2S, (I), (E)-4-methyl-N′-[4-(piperidin-1-yl)benzyl­idene]benzene­sulfono­hydrazide, C19H23N3O2S, (II), and (E)-4-chloro-N′-[4-(piperidin-1-yl)benzyl­idene]benzene­sulfono­hydrazide, C18H20ClN3O2S, (III), derived from aryl­sulfono­hydrazides and 4-(piperidin-4-yl)benzaldehyde have been analysed to investigate the effect of substituents on the structural parameters. All three structures crystallize in monoclinic crystal systems, in the space groups P21/c for (I) and (II), and C2/c for (III). Compound (III) contains two independent mol­ecules in the asymmetric unit and sixteen mol­ecules per unit cell, while (I) and (II) both have one and four mol­ecules, respectively, in their asymmetric units and unit cells. In all cases, the central part of the mol­ecule is twisted at the S atom. In the crystals, the mol­ecules are linked via N—H⋯O hydrogen bonds, forming chains. Two-dimensional fingerprint plots of various inter­atomic contacts show that the major contributions are from H⋯H inter­actions.