Process for preparing 2-(p-fluorophenyl)-2 methyl-propionic acid and 3-(p-fluorophenyl)-2-methylpropionic acid derivatives

Abstract

Process for preparing 3-(p-fluorophenyl)-2-methylpropionic acid and derivatives thereof of the formula (I), ##STR1## in which R is a hydroxy group, a linear or branched (C.sub.1 -C.sub.8)-alkoxy group, an aryloxygroup, an amino group or a (C.sub.1 -C.sub.8)-alkylamino group or a (C.sub.1 -C.sub.8)-dialkylamino group, by a) converting p-fluoroaniline into the p-fluorophenyldiazonium salt of the formula (II) ##STR2## in which X is the equivalent of an anion of an organic or inorganic acid having a pKa value of less than 7, b) reacting the diazonium salt of the formula (II) with a methacrylic acid derivative of the formula (III) ##STR3## in which R is as defined above in the presence of a palladium catalyst, if desired in the presence of a base and/or a solvent, to give the compounds of the formulae (IV) and (V) in which R is as defined above, ##STR4## and c) hydrogenating the resulting compounds of the formulae (IV) and (V) in the presence of a palladium catalyst with hydrogen.

Dependencies are inferred from the claim text.