SYNTHESIS OF NOVEL 4,4'-BENZIDINE DERIVATIVES WITH SULFONIC ACID GROUPS

摘要

Benzidines substituted in the side-chain have been utilized as diamine components of dye intermediates and of aromatic polyimide monomers.Recently 4,4'-benzidine derivatives,with sulfonate groups,have been of great interest as key monomers of the polyimide-electrolyte film in fuel cell systems.These benzidines with 3,3'-bis(sulfoalkoxy)groups have been synthesized by alkylation of commercial 3,3'-dihydroxy-4,4'-benzidine with propane- or butanesul-tones.However,there is no report on a synthetic method for the 2,2'-substituted or alkylsul-fonated ones.We report here a route to 3,3'-bis(sulfomethyl)- and 2,2'-bis(sulfoalkoxy)-4,4'-benzidine via the benzidine rearrangement.