A process for decarboxylating C-C bond formation by reacting carboxylic acid salts with carbon electrophiles in the presence of transition metals or transition metal compounds as a catalyst wherein the catalyst as catalyst system comprises two different transition metals and/or transition metal compounds, wherein one transition metal compound is Cu, wherein the further transition metal compound is Pd, wherein at least one of the metals is stabilized by further ligands from the group of amines, phosphines, N-heterocyclic carbenes, nitriles, olefins wherein the carboxylic acid salt corresponds to the general Formula 1 where n, m, q, p are numbers from 1 to 6 and r is a number from 0 to 6, M is either a metal or an organic compound, R is an organic radical and Y - is an anion, wherein the carbon electrophile corresponds to the general formula R 1 -X where R 1 is an organic radical and the substituent X can be selected from the group of halides from the group of I, Br, Cl, and pseudohalides from the group of toluenesulfonate, methylsulfonate, trifluorosulfonate, trifluoroacetate, carboxylate or [N 2] +, or wherein the carbon electrophile is a carbonyl derivative from the group of carbonyl chloride, carboxylic anhydride, aldehyde, ketone, ester, α,β-unsaturated aldehyde, α,β-unsaturated ketone, α,β-unsaturated ester wherein the substituent R in the general formula 1 is selected from the group of linear, branched and cyclic C 1 -C 20 -alkyl, linear, branched and cyclic C 2 -C 20 -alkenyl, and also C 6 -C 20 -aryl and heteroaryl from the group of pyridine, pyrimidine, pyridazine, pyrazine, triazine, tetrazine, pyrrole, pyrazole, isoxazole, imidazole, oxazole, thiazole, thiophene, furan, and may in turn bear further substituents from the group of linear, branched and cyclic C 1 -C 10 -alkyl, linear, branched and cyclic C 2 -C 20 -alkenyl, and also C 6 -C 10 -aryl and heteroaryl, linear, branched and cyclic C 1- C 10 -alkyloxy or C 1 -C 10 -aryloxy, linear, branched and cyclic C 1- C 10 -alkyl- or C 1 -C 10 -arylaminocarbonyl, linear, branched and cyclic C 1- C 10 -acyl, linear, branched and cyclic C 1 -C 10 -dialkylamino, C 1- C 10 -arylamino, formyl, oxo, thio, hydroxyl, carboxyl, nitro, cyano, nitroso, and halogens such as F, Cl, Br and I, wherein the substituent R 1 of the carbon electrophile is selected from the group of linear, branched and cyclic C 1 -C 20 -alkyl, linear, branched and cyclic C 2 -C 20 -alkenyl, and also C 6 -C 20 -aryl and heteroaryl from the group of pyridine, pyrimidine, pyridazine, pyrazine, triazine, tetrazine, pyrrole, pyrazole, isoxazole, imidazole, oxazole, thiazole, thiophene, furan, and may in turn bear further substituents from the group of linear, branched and cyclic C 1 -C 10 -alkyl, linear, branched and cyclic C 2 -C 20 -alkenyl, and also C 6 -C 10 -aryl and heteroaryl, linear, branched and cyclic C 1- C 10 -alkyloxy or C 1 -C 10 -aryloxy, linear, branched and cyclic C 1 -C 10 -alkyl- or C 1 -C 10 -arylaminocarbonyl, linear, branched and cyclic C 1 -C 10 -acyl, linear, branched and cyclic C 1 -C 10 -dialkylamino, C 1 -C 10 -arylamino, formyl, oxo, thio, hydroxyl, carboxyl, nitro, cyano, nitroso, and halogens such as F, Cl, Br and I.