Process for the preparation of alkenylbenzenecarboxylic acid derivatives and alkenylnaphthalenecarboxylic acid derivatives

A process for the preparation of a compound of the formula I ##STR61## in which m is zero or 1, p is 1 or 2, Z is substituted or unsubstituted phenyl or naphthyl if p=1, and substituted or unsubstituted phenylene or naphthylene if p=2, R is hydrogen, C.sub.1-4 -alkyl, --CH.sub.2 COOR" or --CH.sub.2 CH.sub.2 CN and R' is hydrogen, or, if p=1 and m=zero, can also be C.sub.1-4 -alkyl, --CN or --COOR", but at least one of R and R' must by hydrogen, Y is --CN, --COOR", --CON(R").sub.2 or --COR" and the radicals R", independently of one another, are C.sub.1 -C.sub.12 -alkyl or phenyl, which comprises reacting a compound of the formula II ##STR62## in which Z, m and p are as defined for formula I and X is chlorine, bromine or iodine, with a compound of the formula III or if desired, where p=2, with a mixture of two different compounds of the formula III ##STR63## in which R, R' and Y are as defined for formula I, in the presence of a base and with the addition, as a catalyst, of palladium metal or of a palladium compound which under the reaction conditions forms a phosphorus-free labile palladium(O) compound.