Intramolecular 1,5-S...N σ-hole interaction in (E)-N′-(pyridin-4-ylmethylidene)thiophene-2-carbohydrazide

The title compound, C11H9N3OS, (I), crystallizes in the monoclinic space group P21/n. The molecular conformation is nearly planar and features an intramolecular chalcogen bond between the thiophene S and the imine N atoms. Within the crystal, the strongest interactions between molecules are the N—H...O hydrogen bonds, which organize them into inversion dimers. The dimers are linked through short C—H...N contacts and are stacked into layers propagating in the (001) plane. The crystal structure features π–π stacking between the pyridine aromatic ring and the azomethine double bond. The calculated energies of pairwise intermolecular interactions within the stacks are considerably larger than those found for the interactions between the layers.