1991-59-9Relevant academic research and scientific papers
Effect of fluorocarbon chains on the mesomorphic properties of chiral imines and their complexes with copper(II)
Ocak, Hale,Bilgin-Eran, Belkiz,Tschierske, Carsten,Baumeister, Ute,Pelzl, Gerhard
scheme or table, p. 6995 - 7001 (2010/05/18)
The synthesis and mesomorphism of new chiral imine compounds incorporating a fluorocarbon chain which have calamitic molecular shape and their complexes with copper(II) are reported. The liquid crystalline properties were investigated using polarised optical microscopy, differential scanning calorimetry and X-ray diffraction. Imine compounds with a semifluorinated chain and a short chiral chain show chiral smectic mesophases with dramatically enhanced mesophase stabilities compared to the related hydrocarbon derivatives. In addition, the first examples of mesogenic chiral salicylaldiminate copper(II) complexes carrying semifluorinated alkyl chains at their peripheries have been synthesized and their liquid crystalline properties were investigated.
Disc-like chiral palladium and platinum complexes: Synthesis and mesomorphic properties
Eran, Belkiz Bilgin,Singer, Dirk,Praefcke, Klaus
, p. 111 - 116 (2007/10/03)
ortho-Palladated and -platinated benzalimines are a widely studied novel type of liquid-crystals. These sheet-shaped materials contain two or even four metal atoms and carry eight and twelve flexible side-chains, respectively. Here we present the preparation and mesomorphic properties of dinuclear chiral homologues of such sheet-like compounds. On their own, the chiral members of the dinuclear cyclopalladated series exhibit no liquid-crystalline properties, but show mesophase inductions (Colh-phase) in mixtures with an electron-acceptor, e.g.,2,4,7-trinitroflourenone (TNF). A diplatinated chiral analogue, however, monotropically exhibits the cholesteric nematic discotic (ND/*) type of mesophase. Mixtures of this platinum nematogen with TNF also show the induction of a columnar mesophase (Colh) due to charge-transfer interactions.
A Comprehensive Approach to (S)-(-)-2-Methyl-1-Butanol as a Convenient Precursor for Synthesis of Chiral Liquid Crystals
Kaszynski, P.,Jawdosiuk, M.
, p. 21 - 38 (2007/10/02)
The chemistry of S-(-)-2-methyl-1-butanol leading to chiral liquid crystals (CLC) and their intermediates is summarized and new facile synthetic methods are described.Efficiency of the presented methods is discussed and illustrated with syntheses of several known and new CLC as well as the corresponding chiral intermediates.The newly synthesized chiral compounds display cholestic and smectic phases.Keywords: (S)-(-)-2-methyl-1-butanol, (S)-(+)-methyl-1-butyl benzenesulfonate, chiral liquid crystals, smectic C
Chiral Mesogenic Compounds: Carbocyclic and Heterocyclic Schiff Bases
Barbera, J.,Melendez, E.,Serrano, J. L.,Sierra, M. T.,Ezcurra, A.,Jubindo, M. A. Perez
, p. 151 - 158 (2007/10/02)
Five different chiral p-substituted anilines derived from 4-aminobenzoic acid and from 4-aminophenol were condensed with four carbocyclic and heterocyclic aldehydes in order to obtain chiral Schiff bases resembling DOBAMBC and HOBACPC.With the exception of the pyridine-3-carboxaldehyde derivatives, the compounds are mesomorphic.Some of the compounds exhibit ferroelectric SC* phases, and all exhibit SA or Ch mesophases on heating.Benzaldehyde and pyridine-2-carboxaldehyde derivatives show similar mesomorphic behavior, as was to be expected from MNDO semiempirical calculations.Values of the spontaneous polarization of certain compounds were measured.
