The formylation of aromatic compounds such as benzene, toluene, xylenes, mesitylene, indan, tetralin, fluorobenzene, chlorobenzene, and bromobenzene was carried out in HS03F- SbF5 under atmospheric CO pressure at 0 OC. In HS03F-SbF5, both formylation and sulfonation took place to give formyl and sulfonyl compounds. In the case of alkylbenzenes, including toluene, xylenes, mesitylene, and tetralin, formylalkylbenzenesulfonyl fluorides, ...
