Synthesis and liquid-crystalline behaviour of tetrakis- and octakis(13,17-dioxa nonacosane-15-sulfanyl)phthalocyanines

Abstract

Tetra- and octa(13, 17-dioxa nonacosane-15-sulfanyl) substituted metal free- and Ni(ll) phthalocyanines have been synthesized from the corresponding phthalonitrile derivatives in the presence the anhydrous metal salt(NiCl2) or a strong organic base. The new compounds have been characterised by elemental analyses, IR, NMR and electronic spectroscopy and mass spectra. The mesogenic properties of these new materials were studied by differential scanning calorimetry(DSC), optical microscopy and X-ray investigations. All compounds show a discotic mesophase in an extremely large temperature interval including room temperature. X-ray diffraction patterns of the mesophases confirm that tetra-substituted compounds(5a, 5b) form a hexagonal ordered columnar mesophases(D-ho), whereas octa-substituted compounds(7a, 7b) lend to centered rectangular disordered columnar mesophases(D-rd).