Patent ID: 7329779

Claim:
Process for preparing arylsulphonic anhydrides of the general formula (I), in which R 1 to R 5 are each independently hydrogen, C 1 -C 12 -alkyl, C 1 -C 12 -fluoroalkyl, C 1 -C 12 -alkoxy, C 1 -C 12 -fluoroalkoxy, C 4 -C 18 -aryl or C 5 -C 19 -arylalkyl, halogen, NO 2 , wherein arylsulphonic acids of the general formula (II), in which R 1 to R 5 are each as defined for the general formula (I), are reacted with thionyl chloride in at least one optionally substituted cyclic or acyclic aliphatic hydrocarbon as a solvent.