PROCESS FOR THE PREPARATION OF ARYLAMIDES OF HETEROAROMATIC CARBOXYLIC ACIDS

A process is described for the preparation of arylamides of heteroaromatic carboxylic acids of the formula: (see formula I) in which each A n is nitrogen or CR n (n = 1-5), with the proviso that at least one of the ring members is nitrogen and that two nitrogen atoms are not bonded directly to one another; R1 to R5, if present, independently of one another are each hydrogen, C1-4-alkyl or aryl, it also being possible for one of the substituents R1 to R5 to be a group of the formula -OR, in which R is an optionally substituted aromatic or heteroaromatic radical; R6 is hydrogen or C1-4-alkyl; and R7 is an optionally substituted aromatic or heteroaromatic radical. The amides are obtained from the corresponding heteroaromatic halogen compounds, the corresponding aromatic amines and carbon monoxide in the presence of a palladium diphosphine complex as catalyst. Compounds of this class, especially those in which one of the substituents R1 to R5 is an aryloxy group, are important herbicides.