The crystal structure of 2′,6′-dichloro-4-dimethylaminoazobenzene

A monoazo dye, 2′,6′-dichloro-4-dimethylaminoazobenzene (C₁₄H₁₃Cl₂N₃) was synthesized and characterized by X-ray diffraction, IR, ¹H NMR, and elemental analysis. The title molecule crystallizes in the monoclinic system space group P2₁/c (#14), a = 10.782(1), b = 8.9610(9), c = 15.108(2) Å, β = 103.008(5)°, V = 1422.2(3) Å³, Z = 4. The title molecule is not planar and takes trans-geometry and the two phenyl rings are twisted around the central linkage in opposite directions. In the crystal, molecules are interacted through π?π interaction, forming ‘double chains’ along 1 ?1 0]. The ‘double chains’ are extended along 001] through H-Bond C11–H6?Cl2, C5–H3?Cl1 forming double layers (110), which are in turn interacted by C3–H1?Cl1 H-Bond 010], forming crystals. The molecular geometry has been calculated using the ab initio restricted Hartree–Fock and density functional method (B3LYP) with 6-311G** basis set. The optimized geometric parameters obtained by two methods are similar and in good agreement with the experimental values.