Synthesis of meta-arylphenol derivatives via acid-promoted rearrangement of cyclohexadienones

Abstract

A highly effective strategy for the synthesis of meta-arylphenol derivatives through the selective rearrangement of 4-alkyl-4-aryl-2,5-cyclohexadienones under metal-free conditions was developed, in which acid-promoted [1,2]-migration of the aryl group at C-4 occurred exclusively when the alkyl group at C-4 was a methyl group. Treatment of 4-methyl-4-aryl-2,5-cyclohexadienones with 37% HCl in Ac₂O at room temperature provided polysubstituted meta-arylphenyl acetates in 75–94% yields. The application of this protocol in the synthesis of polycyclic aromatic compounds was also described.