A process for the preparation of dihalodiphenylsulfones such as 4,4′-dichlorodiphenyl sulfone or 4,4′-bis-(4-chlorophenylsulfonyl)biphenyl with high regioselectivity, at low temperature and in the absence of toxic reagents by reacting together at least one acid, at least one fluorinated anhydride and at least one halobenzene. The invented process is particularly suited for the manufacture of 4,4′-dichlorodiphenyl sulfone.