The synthesis and transition temperatures of benzoate ester derivatives of 2‐fluoro‐4‐hydroxy‐and 3‐fluoro‐4‐hydroxybenzonitriles

The synthesis and the liquid‐crystal temperatures of sixty 4‐cyano‐2‐fluorophenyl and 4‐cyano‐3‐fluorophylen 4‐substituted benzoates are described. The nematic‐isotropic liquid transition temperatures of the most of these novel esters are only marginally lower than those of the corresponding esters containing an H‐atom in place of the F‐substituent. In several instances, the clearing points of the F‐substiuted‐phenyl esters are higher than those of the non‐substituted‐phenyl esters. The nematic ranges of several of the new esters are markedly broader than those of the analogous non‐F‐substituted‐phenyl esters.