1-(5-Chloro-6-fluoro-1,3-benzothiazol-2-yl)hydrazine

Expected and unexpected products of reactions of 2-hydrazinylbenzo-thia-zole with 3-nitro-benzene-sulfonyl chloride in different solvents

The syntheses and crystal structures of 2-[2-(propan-2-yl-idene)hydrazin-yl]-1,3-benzo-thia-zol-3-ium 3-nitro-benzene-sulfonate (C10H12N2S+·C6H4NO5S-), (I), 2-[2-(3-nitro-benzene-sulfon-yl)hydrazin-yl]-1,3-benzo-thia-zole (C13H10N4O4S2), (II) and 2-[2-(3-nitro-benzene-sulfon-yl)hydrazin-yl]-1,3-benzo-thia-zol-3-ium 3-nitro-benzene-sulfonate (C13H11N4O4S2+·C6H4NO5S-), (III) are reported. Salt (I) arose from an unexpected reaction of 2-hydrazinylbenzo-thia-zole with the acetone solvent in the presence of 3-nitro-benzene-sulfonyl 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 inter-act by way of short π-π stacking inter-actions between the thia-zole rings [centroid-centroid separation = 3.4274 (18) Å]. In (II), which crystallizes with two neutral mol-ecules in the asymmetric unit, the mol-ecules are linked by N-H⋯N and N-H⋯On (n = nitro) hydrogen bonds to generate [[Formula: see text]1[Formula: see text]] chains, which are cross-linked by C-H⋯O and π-π stacking inter-actions. The crystal of (III) features centrosymmetric tetra-mers (two cations and two anions) linked by cooperative N-H⋯O hydrogen bonds; C-H⋯O and π-π inter-actions occur between tetra-mers.

1-(6-Chloro-1,3-benzothiazol-2-yl)-2-[1-(4-methoxyphenyl)ethylidene]hydrazine

The asymmetric unit of the title compound, C₁₆H₁₄ClN₃OS, contains two independent mol­ecules (A and B) linked into dimers via N—H⋯N hydrogen bonds. The 1,3-benzothia­zol-2-yl ring system and the benzene ring form dihedral angles of 17.08 (8) and 8.63 (7)° in mol­ecules A and B, respectively.