Vicarious Nucleophilic Aromatic Substitution via Trapping of an .alpha.-Ketosulfonium Ion Generated by Pummerer-Type Rearrangement of 2-(Phenylsulfinyl)phenols: Preparation of Biaryls

A new method for the nucleophilic substitution of phenols at the ortho position has been developed which uses as the key step the trapping of an α-ketosulfonium salt generated by a Pummerer rearrangement of 2-(phe- nylsulfinyl)phenols. In addition to preparing 2-halo- and 2-(acyloxy)- phenols, this «vicarious substitution» also allows the preparation of biaryls in fair yield