Expected and unexpected products of reactions of 2-hydrazinylbenzothiazole with 3-nitrobenzenesulfonyl chloride in different solvents

The syntheses and crystal structures of 2-[2-(propan-2-yl­idene)hydrazin­yl]-1,3-benzo­thia­zol-3-ium 3-nitro­benzene­sulfonate (C10H12N2S+·C6H4NO5S−), (I), 2-[2-(3-nitro­benzene­sulfon­yl)hydrazin­yl]-1,3-benzo­thia­zole (C13H10N4O4S2), (II) and 2-[2-(3-nitro­benzene­sulfon­yl)hydrazin­yl]-1,3-benzo­thia­zol-3-ium 3-nitro­benzene­sulfonate (C13H11N4O4S2+·C6H4NO5S−), (III) are reported. Salt (I) arose from an unexpected reaction of 2-hydrazinylbenzo­thia­zole with the acetone solvent in the presence of 3-nitro­benzene­sulfonyl chloride, whereas (II) and (III) were recovered from the equivalent reaction carried out in methanol. The crystal of (I) features ion pairs linked by pairs of N—H...Os (s = sulfonate) hydrogen bonds; adjacent cations inter­act by way of short π–π stacking inter­actions between the thia­zole rings [centroid–centroid separation = 3.4274 (18) Å]. In (II), which crystallizes with two neutral mol­ecules in the asymmetric unit, the mol­ecules are linked by N—H...N and N—H...On (n = nitro) hydrogen bonds to generate [\overline{1}1\overline{1}] chains, which are cross-linked by C—H...O and π–π stacking inter­actions. The crystal of (III) features centrosymmetric tetra­mers (two cations and two anions) linked by cooperative N—H...O hydrogen bonds; C—H...O and π–π inter­actions occur between tetra­mers.