SYNTHESIS AND MESOMORPHIC PROPERTIES OF SOME 3-SUBSTITUTED-4-CYANOPHENYL ESTERS, 4'-CYANO-3-SUBSTITUTED-4-BIPHENYL ESTERS OF 4-(TRANS-4-ALKYLCYCLOHEXYL) BENZOIC, 4-ALKYL-3-SUBSTITUTED BIPHENYL-4'-CARBOXYLIC, TRANS-4-ALKYLCYCLOHEXANECARBOXYLIC AND 4-ALKYLBENZOIC ACIDS AND ELECTROOPTIC PARAMETERS OF LIQUID-CRYSTALLINE MIXTURES CONTAINING THESE COMPOUNDS

The reaction of trans-4-alkylcyclohexanecarboxylic acid chlorides, 4-alkylbenzoic, 4-(trans-4-alkylcyclohexyl)-benzoic, 4-alkyl-3-substituted biphenyl-4'-carboxylic acids (I) with 4-hydroxy-3'-substituted benzonitriles (IIa-d) and 4-hydroxy-3'-substituted-4'-cyanobiphenyls (IIe and g) has produced the corresponding esters (IIIa-v). The mesomorphic properties of the esters and electrooptic and dynamic parameters of the mixtures containing these compound have been studied. It has been shown that the liquid-crystalline mixtures containing 4-cyano-3-substituted-4'-biphenyl esters of 4-alkylbenzoic and trans-4-alkyl-cyclohexanecarboxylic acids have higher threshold voltages and saturation voltages in comparison with the analogous mixtures containing 4-cyano-3-substituted phenyl esters of 4-(trans-4-alkylcyclohexyl)benzoic acids.