Liquid Crystalline Phases through Intermolecular Hydrogen Bonding Formed in a Mixture of Phenol Derivatives and 4,4′-Bipyridine

Abstract

Smectic liquid crystalline phases are formed due to the intermolecular hydrogen bonding in a binary mixture of phenol derivatives and 4,4′-bipyridine as the length of the terminal alkyl or alkoxyl chains are increased.

Nichtkovalente Synthese mit Wasserstoffbrücken

“…[453] Cyclovoltammetrisch wurde gezeigt, dass die Nanoröhren als selektive Ionenkanäle fungieren, da nur Redoxpaare, die klein genug sind, um die Kanäle zu passieren, redoxaktiv waren. [457] [465] Diesen Studien folgten verwandte Systeme, die auf Phenol-Stilbazol-, [466] Carbonsäure-Stilbazol-, [467] Phenol-Pyridin-, [468] Alkohol-Imidazol- [469] und Carbonsäure-Amidopyridin-Wechselwirkungen [470] basieren. [454] Nach selektiver N-Methylierung einer Seite des cyclischen Peptids können nur noch dimere Strukturen gebildet werden.…”

Hydrogen‐Bonded Systems

“…The structure of the complex, which does not have an overall rod shape, is unique for calamitic liquid crystals. This supramolecular mesogen is attached to the polyacrylate backbone [44]. For polymeric complex 25, a monotropic smectic phase was observed between 98 and 80 "C. It should be noted that in this polymeric structure the mesogenic group is expected to align perpendicular to the polymer chain.…”

“…Doubly hydrogen-bonded supramolecular mesogenic complexes have been derived by the formation of the hydrogen bonds between 2-aminopyridyl and carboxylic acid moieties [43,44]. Complex 24 sharply melts A, #O c 24 CH3 at 90 "C and exhibits a monotropic smectic B phase from 83 to 67°C [43].…”

“…Variable-temperature electronic spectroscopy shows that ionic hydrogen-bonded state by proton transfer is stabilized in the mesophase. The induction of smectic phases has also been observed for the mixture of 4,4'-bipyridine and 4-alkoxyphenol [44]. Liquid-crystalline polymer blends (29) involving phenol/pyridine interactions have been prepared from a polyester containing a pyridyl lateral group and poly(4-vinylphenol) [45].…”

Effect of Lateral Substitution on the Electronics and Phase Transitions of Stilbazoles, Benzoic Acids, Phenols, and Hydrogen Bonded Mixtures

“…The melting points of model mixtures H and I are identical, suggesting the disruption in packing is almost entirely the result of stilbazole ring twisting. Lateral substitution on the phenol ring in mixture K results in a significant melting point depression (relative to J); however, unlike mixture A, the weaker phenol-stilbazole hydrogen bond [56,57] in mixture J cannot form the rigid mesogenic core required to form a calamatic hydrogen bonded liquid crystal. Lateral substitution still disrupts intermolecular donor-acceptor hydrogen bonding in mixture K, resulting in a significant melting point depression relative to that in mixture J.…”