ISSN:
0021-8383
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Liquid-Crystalline Heterocycloalkanes. III. Synthesis and Liquid-Crystalline Properties of Substituted 1,3-DioxadecalinesLiquid-crystalline 2-substituted and 2,6-disubstituted 1,3-dioxadecalines (4 - 6) were synthesized by acid-catalyzed acetalization of trans-2-hydroxymethylcyclohexanol (1) or trans-4-alkyl-trans-2-hydroxymethylcyclohexanoles (2) with aldehydes 3 whereby the desired transisomers were formed only. The syntheses of the various aldehydes are also described.Special attention is drawn on the evolution of mesogenic properties of the titlecompounds 4 - 6 in comparison with known decalines and 1,3-dioxanes.It was found that the clearing temperatures of the synthesized 1,3-dioxadecalines are always lower than those of the corresponding decaline derivatives, due to the deformation of the decalineringsystem by the introduction of two oxygen-atoms. The comparison of 1,3-dioxanes and 1,3-dioxadecalines shows that the dioxadecaline ringsystem tends to suppress smectic mesophases in favour of nematics. A first example of a liquid crystalline cis-fused 1,3-dioxadecaline (8) is described, too.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/prac.19883300102
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