Crystal structures and Hirshfeld surface analyses of (E)-1-[1-(4-tert-butylphenyl)-2,2-dichloroethenyl]-2-phenyldiazene, (E)-1-[1-(4-tert-butylphenyl)-2,2-dichloroethenyl]-2-(4-methylphenyl)diazene, (E)-1-[1-(4-tert-butylphenyl)-2,2-dichloroethenyl]-2-(4-methoxyphenyl)diazene and (E)-1-[1-(4-tert-butylphenyl)-2,2-dichloroethenyl]-2-(3-methylphenyl)diazene

Abstract

The crystal structures and Hirshfeld surface analyses of four similar azo compounds are reported. (E)-1-[1-(4-tert-Butylphenyl)-2,2-dichloroethenyl]-2-phenyldiazene, C18H18Cl2N2, (I), and (E)-1-[1-(4-tert-butylphenyl)-2,2-dichloroethenyl]-2-(4-methylphenyl)diazene, C19H20Cl2N2, (II), crystallize in the monoclinic space group C2/c with Z = 8, and (E)-1-[1-(4-tert-butylphenyl)-2,2-dichloroethenyl]-2-(4-methoxyphenyl)diazene, C19H20Cl2N2O, (III), in the monoclinic space group P21/c with Z = 4. (E)-1-[1-(4-tert-Butylphenyl)-2,2-dichloroethenyl]-2-(3-methylphenyl)diazene, C19H20Cl2N2, (IV), crystallizes in the triclinic space group P\overline{1} with Z = 4 and comprises two molecules (A and B) in the asymmetric unit. In the crystal structures of (I) and (II), molecules are linked by C—H...π and C—Cl...π interactions, forming layers parallel to (\overline{2}02), while molecules of (III) are linked by C—H...O contacts, C—H...π and C—Cl...π interactions forming layers parallel to (\overline{3}02). The stability of the molecular packing is ensured by van der Waals forces between these layers. In the crystal structure of (IV), molecules are linked by C—H...π and C—Cl...π interactions, forming a tri-periodic network.

Keywords

• crystal structure
• azo compounds
• c—h...π and c—cl...π interactions
• hirshfeld surface analysis