PREPARATION METHOD OF TRIFLUOROMETHYL-SUBSTITUTED BIPHENYLCARBOXYLIC ACID AND NOVEL TRICHLOROMETHYL- AND TRIFLUOROMETHYL-SUBSTITUTED BIPHENYLCARBONITRILES

摘要

PURPOSE: A method for preparing a trifluoromethyl-substituted biphenylcarboxylic acid and novel trichloromethyl- and trifluoromethyl-substituted biphenylcarbonitriles are provided, which method can be carried out in the industrial scale. CONSTITUTION: The method comprises the steps of converting the methyl-substituted biphenylcarbonitrile of the formula 4 into the corresponding trichloromethyl-substituted biphenylcarbonitrile of the formula 3; converting the trichloromethyl group into the trifluoromethyl group to obtain the trifluoromethyl-substituted biphenylcarbonitrile of the formula 2; and hydrolyzing the compound of the formula 2 to obtain the trifluoromethyl-substituted biphenylcarboxylic acid of formula 1, wherein X¬1 and X¬2 are the same or different each other and are H, Cl or F. Preferably the conversion of the trichloromethyl group into the trifluoromethyl group is carried out by reacting the trichloromethyl-substituted biphenylcarbonitrile of the formula 3 with anhydrous HF.