abstract |
The invention relates to a process for the preparation of acid chlorides by reaction of carboxylic acids, carboxylic anhydrides, cyclic carboxylic esters or sulfonic acids with phosgene in the presence of a catalytic amount of a compound from the group consisting of N,N,N',N'-tetrasubstituted amidinium halides (I), N,N,N'-trisubstituted amidinium hydrohalides (II) and N,N,N'-trisubstituted amidines (III). |