Synthesis and characterization of novel liquid and liquid crystalline phthalocyanines

Abstract

Peripheral and non-peripheral tetra(13,17-dioxanonacosane-15-hydroxy) substituted metal free-, Ni(II) and Zn(II) phthalocyanines have been synthesized from the corresponding phthalonitrile derivatives in the presence of the anhydrous metal salt (NiCl2 and Zn(OOCCH3)(2)) or a strong organic base. The new compounds have been characterised by elemental analyses, IR, NMR, mass spectra and electronic spectroscopy. The mesogenic properties of these new materials were studied by differential scanning calorimetry (DSC), optical polarised microscopy and X-ray investigations. The effects of peripheral or non-peripheral substitution of (13,17-dioxanonacosane-15-hydroxy) to the phthalocyanine ring are also investigated. It is found out that non-peripheral substituted phthalocyanine derivatives (4a-c) are liquid at room temperature whereas, peripheral substituted phthalocyanine derivatives (7a-c) exhibit ordered discotic hexagonal columnar mesophases (Col(h)) at room temperature. Copyright (c) 2004 Society of Porphyrins & Phthalocyanines.