Liquid crystalline substances

摘要

New liquid-crystalline esters of the 4-[(4-alkyl-cyclohexyl)-methyl]-benzoic acids or cyclohexanecarboxylic acids which are suitable for electro-optical displays have the general formula <IMAGE> or <IMAGE> wherein R1=CnH2n+1 R2=H, <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> <IMAGE> +TR <IMAGE> wherein n=an integer from 1 to 10, m=an integer from 1 to 10, S=an integer from 1 to 10. The aforementioned esters are produced by converting the corresponding 4-alkylcyclohexanecarboxylic acid chloride according to Friedel-Crafts with benzene, reduction of the corresponding ketones to 4-alkyl-cyclohexyl-methyl-benzene, Friedel-Crafts acylation with acetyl chloride and oxidation with bromine to the 4-[(4-alkyl-cyclohexyl)-methyl]-benzoic acids, which are esterified according to conventional methods with substituted cyclohexanols or phenols or are hydrogenated with hydrogen and Raney-Nickel under high-pressure to 4-[(4-alkyl-cyclohexyl)-methyl]-cyclohexanecarboxylic acids, and then are esterified according to conventional procedures with substituted cyclohexanols or phenols.