Liquid Crystals With Hydroaromatic and Hydroheterocyclic Structures

Abstract

1,4-disubstituted cyclohexanes with transconfiguration and the N,N'-disubstituted piperazine system are able to function as a nucleus in liquid crystals. These characteristics are described in the case of nine homologous series (1-9) of corresponding compounds

Crystal Structures of N,N’-bis(5-Dodecyloxytropon-2-yl)piperazine and N,N’-bis(4-Butoxyphenyl)piperazine

“…Copies of the data can be obtained free of charge via http://www.ccdc.cam.ac.uk/conts/retrieving.html (or from the Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge, CB2 1EZ, UK; Fax: +44 1223 336033; e-mail: deposit@ccdc.cam.ac.uk). Crystal data for 1: C42H66N2O4, monoclinic, P21/c, a =38.288(9) Å, b = 7.187(2) Å, c = 6.924(2) Å, β = 91.42(2)°, V = 1904.6(8) Å 3 , Z = 2, Mr = 662.99, Dx = 1.156 g cm −3 , μ = 5.659 cm −1 , T = 296(2) K, R1[I > 2σ(I)] = 0.0764, wR = 0.1943, S = 1.011.Preparation of N,N'-Bis(4-butoxyphenyl)piperaziene (2)N,N'-Bis(4-butoxyphenyl)piperaziene (2) was synthesized by the reaction of 4-butoxyaniline and 1,2-dibromoethane in the presence of Na2CO3, as reported in a previous paper 10. Yield 48%, Cr•117•SmC•128•Iso, colorless prisms.…”

From the discovery of the partially bilayer smectic A phase to blue phases in polar liquid crystals

“…Significant milestones including the investigations undertaken by Hoffmann La Roche on cyanophenyl benzoates 12 [7] in parallel to Gray's studies, the investigations of the esters of 4-alkylcycloalkanecarboxylic acid 6 [8,9] performed at the University of Halle, as well as the preparation of 4-(4-cyanophenyl) alkylcyclohexanes 3 (PCH) [10] and 4-cyano-4ʹ-alkylbicyclohexanes 5 (CCH) [11] and their analogues terminated with F or OCF 3 or an alkyl or an alkoxy group performed by Merck very soon after created the foundations of the contemporary trends in the science and technology of LCs. [12][13][14] Although nowadays one knows many tens of thousands of LCs, nCB, nOCB and, especially 5CB are still the most frequently studied LC compounds.…”

Die selektive Hydrierung von 4-substituierten Phenolderivaten zu den Cyclohexanon-Analogen – Katalysatoroptimierung und Kinetik

“…Eine Verbindung muss keine polare Endgruppe aufweisen, um flüssigkristallines Verhalten zeigen zu können [1]. Jedoch ist das Vorhandensein solcher Kopfgruppen in LCD-Substanzen notwendig, um die Orientierung der Moleküle relativ zum Display durch Anlegen eines elektrischen Feldes (gemäû deren Polarisierbarkeit) verändern zu können.…”

“…Auflage im Jahr 1997 [1]. In regelmäûigen Zeitabständen werden die erzielten Fortschritte im VDI-Wärmeatlas analysiert und Korrelationen zur Berechnung der Wärmetransportparameter empfohlen.…”