Hideyuki Kihara

Supramolecular ferroelectric liquid crystals. Hydrogen-bonded complexes between benzoic acids and chiral stilbazoles

Abstract Supramolecular ferroelectric liquid crystalline complexes have been obtained from 4-alkoxybenzoic acids and optically active trans-4-substituted-4′-stilbazoles. Chiral smectic C phases are induced by the formation of supramolecular mesogenic structure through the selective intermolecular hydrogen bond between the achiral benzoic acids and the chiral non-mesogenic stilbazoles.

Induction of a cholesteric phase via self-assembly in supramolecular networks built of non-mesomorphic molecular components

Supramolecular hydrogen-bonded networks have been prepared by self-assembly of a chiral bifunctional H-bond acceptor and achiral trifunctional H-bond donors. A stilbazole dimer, (R)-1,2-bis{4-\[2-(4-pyridyl)ethenyl]phenoxy}propane (1) has been synthesized for use as a chiral component for cholesteric networks. Compound 1 has been complexed with tri functional H-bond donors, p,q-bis{2-\[2-(4-carboxyphenoxy)ethoxy]ethoxy}benzoic(2-6) \[p, q =2,4 (2); 2,5 (3); 2,6 (4); 3,4 (5); 3,5 (6)], maintaining the 1 :1 donor/acceptor group stoichiometry. With the exception of the complex from 1 and 6, these H-bonded complexes exhibit cholesteric phases and glass transition behaviour, while all individual components are non-mesomorphic. For example, the H-bonded complex consisting of 1 and 2 shows a cholesteric phase from 75 to 184 C on heating. These results suggest that supramolecular liquid crystalline networks with macroscopic helical structures have been formed by intermolecular hydrogen bonds between non-mesomorph...

On the mesomorphism of hydrogen bonded complexes formed between decyloxystilbazole and phthalic acid

Further investigation of the mesomorphism of hydrogen bonded complexes formed between alkoxystilbazoles and benzenedicarboxylic acids has led to a reinterpretation of the phase behaviour. We have found unexpectedly that the most stable complex is at an equimolar ratio.