METHOD FOR THE CARBONYLATION OF PENTENOIC ACID AND DERIVATIVES THEREOF

Process for the carbonylation of n-pentenoic acid or its derivatives of the formula (I)where R is -CN or COOR where R is hydrogen, alkyl or aryl by reaction of a compound of the formula (I) with carbon monoxide and a compound (II) containing a hydroxyl group in the presence of a catalyst system, wherein the catalyst system is obtainable by reaction ofa) a source for a metal ion of a metal (III) of the 8th subgroup of the Periodic Table of the Elements withb) a bidentate phosphine ligand of the formula (IV)whereR , R , R , R , R , R , R , R , R , R , R , R independently of one another is an organic radical which in each case contains a carbon atom, via which the respective radical is linked to the relevant tertiary carbon atom mentioned in formula (IV);L , L independently of one another are a lower alkylene group;X is an arylene group.