NEW MATERIAL:A compound expressed by formula I (R is H or 1-10C alkyl). EXAMPLE:4-Cyanophenyl 4-[trans-4'-(trans-4''-propylcyclohexyl)cyclohexyl]benzoate. USE:A liquid crystal composition having about +8 dielectric anisotropy value and good stability to moisture, heat, light, etc., changing the threshold voltage and saturation voltage of the composition not so much. PROCESS:Bromobenzene is reacted with metallic magnesium, and the resultant product is then reacted with a compound expressd by formula II to afford a compound expressed by formula III. The resultant compound expressed by formula III is then dehydrated in the presence of a catalyst and then hydrogenated to give a compound expressed by formula IV, which is then halogenated with iodic acid, etc. and cynogenated with cuprous cyanide to afford a compond expressed by formula V. The resultant compound expressed by formula V is hydrolyzed in an aqueous solution of KOH to give a benzoic acid derivative expressed by formula VI, which is then converted into an acid chloride, and reacted with 4-cyanophenol to afford the aimed compound expressed by formula I .
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