Crystal structure of N-(1,3-benzothiazol-2-yl)-4-iodobenzene-1-sulfonohydrazide: the importance of unusual N-H···π and I···π interactions on the supramolecular arrangement

The 2-hydrazinyl-1,3-benzothiazole derivatives are precursors for synthesis of several compounds of technological interest, including the Bt-NH-N=CHR₁(R₁= alkyl, aryl, heteroaryl), derivatives. Usually when Bt-NH-NH₂ is allowed to react with a benzenesulfonyl chloride the substitution is observed in the terminal nitrogen of the arenehydrazine unit, but when 4-iodophenyl sulfonyl chloride (4-IC₆H₄SO₂Cl) was used,the product isolated was the title compound as confirmed by Rx-analysis. The determination of the crystal structure revealed that the definition of the arrangement was driven by N-H···π,C-I···Π and S2—O21···π interactions instead of the classic O···H—N hydrogen bonds. The interactions were confirmed by HS analysis. Interaction energycalculations showedthat the π interactions-based motifs play an important role in the supramolecular arrangement ,contributing about 60% to the total energy of the lattice. DFT calculations showed thatthe energy of the C-I···π dimer is complemented with contributions of π···πstacking and N-H···π interaction between the primary amine and the thiazole aromatic ring.