Process for the manufacture of dihalodiphenylsulfones starting from organic acids

摘要

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, sulfur trioxide and at least one halobenzene. The invented process is particularly suited for the manufacture of 4,4′-dichlorodiphenyl sulfone.