Synthesis, electronic properties and packing modes of conjugated systems based on 2,5-di(cyanovinyl)furan or thiophene and imino-perfluorophenyl moieties

Abstract

The synthesis, the electronic properties and the solid state arrangements of conjugated systems associating pentafluorophenyl units linked via azomethine bonds to a central 2,5-di(cyanovinyl)-thiophene or furan moieties have been investigated. The crystal structures of the two compounds are analyzed in terms of intermolecular interactions involving hydrogen and halogen bonding, π–π stacking and donor–acceptor interactions. Both structures reveal similar π-stacking of the molecules with nevertheless a more compact packing mode for the furan derivative. Moreover this structure is stabilized by several F⋯F interactions between the columns of molecules. By contrast for the thiophene derivative, the structure requires the insertion of CH₂Cl₂ to be stabilized via Cl⋯F interactions.