Lewis Acids Catalysed Fries Rearrangement of Isopropylcresol Esters

Article abstract of DOI:10.1007/BF00809536

In the course of the Fries rearrangement, aluminium chloride frequently induces migration or elimination of alkyl groups.The results obtained with titanium tetrachloride for the synthesis of vicinal o-hydroxyketones are compared with those obtained with aluminium chloride for some aliphatic and aromatic esters of isopropylcresols.In order to understand the migration and elimination processes occurring, the stabilities of the o-hydroxyketones are studied in the presence of aluminium chloride at different temperatures.Furthermore, all-vicinal o-hydroxyketones were prepared by the Fries rearrangement of 6-tert-butyl-p-thymol with titanium tetrachloride.