Discotic liquid crystals of transition-metal complexes. Part 18.—Discotic liquid crystalline behaviour in phthalocyanine compounds substituted by steric hindrance groups at the core

Abstract

Phthalocyanine compounds substituted with steric hindrance groups have been synthesized: octakis(2-ethyl-hexy1)phthalocyanine (1 b) and bis[octakis(4-octadecyloxyphenyl)phthalocyaninato]lutetium(111) complex (2d). These compounds exhibit a wide temperature range of discotic liquid-crystalline properties. Each of these compounds shows a discotic tetragonal disordered columnar mesophase (Dtet.d) or a discotic plain rectangular disordered columnar mesophase [Drd(P2rn)] with a lattice very close to tetragonal. This Drd(P2rn) phase is a novel discotic mesophase that has not been reported to date. It was found that the introduction of the steric hindrance groups, 2-ethylhexyl (b) and 4-octadecyloxyphenyl (d), tend to induce the appearance of the Dtet.d phase.

Effect of Core Twisting on Self‐Assembly and Optical Properties of Perylene Bisimide Dyes in Solution and Columnar Liquid Crystalline Phases

“…The five Bragg reflections observed in the small angle region can be indexed according to a two-dimensional centered rectangular lattice (c2mm) with satisfactory accuracy (Table S2 in the Supporting Information). [32] In the wide angle region, there are two diffuse scatterings and one more sharp scattering. The comparatively sharp peak at 2q = 218 (peak b) is indicative of a periodicity in the structure with a repeat distance of 0.43 nm.…”

Discotic liquid crystals of transition metal complexes: 28. Temperature-dependent electronic spectra and X-ray structural analysis of discotic liquid crystalline bis(octakisdodecyloxyphthalocyaninato)lutetium(III) complex

“…1) was synthesized by Simon and co-workers in 1985 [8]. Since then the derivatives 1c [2] 1d [9] and 1e [10] have been synthesized so far. The mesomorphism and AC conductivity of bis(octakisdodecyloxyphthalocyaninato)lutetium(III) (1c in Fig.…”

Discotic liquid crystals of transition metal complexes 49: establishment of helical structure of fullerene moieties in columnar mesophase of phthalocyanine-fullerene dyads

“…It may be attributable to freedom of rotation of the dyad, taking our previous work [36] into consideration. As illustrated in this figure, the columns formed by the shorter-spacer-substituted dyads 3a,b (n = 6, 8; M = Cu) can freely rotate to show a Col h mesophase.…”