Synthesis and thermotropic properties of hydroxy and silyloxy axially substituted phthalocyanines

Novel boron(III) subphthalocyanines 5-8 with six lipophilic alkylthio chain s at the peripheral sites, bearing hydroxy or triethylsilyloxy groups in th e axial position, have been synthesized and their thermotropic properties h ave been studied. These compounds are gelatinous materials at room temperat ure and gradually soften as the temperature is raised up to a point at whic h high fluidity typical of classical liquids is observed. By the usual tech niques employed for the study of thermotropic behaviour (polarizing microsc opy, DSC and X-ray diffraction), no liquid crystalline properties have been found. Instead, the compounds have an amorphous structure (i.e. behave as isotropic materials) throughout the temperature range studied. They could b e designated as liquid subphthalocyanines. Copyright (C) 2000 John Wiley & Sons, Ltd.