Reversal of Reactivity of Heyns Intermediate for the Concise Synthesis of Substituted 3-Hydroxyquinolines

An efficient and general method for the synthesis of 3-hydroxyquinolines has been achieved from <i>o</i>-acylanilines and α-hydroxyketones in good yields. The strategy involves the intramolecular reverse trapping of the <i>in situ</i> generated aminoenol intermediate with an electrophilic carbonyl, <i>viz</i>. an interrupted Heyns rearrangement, followed by aromatization. Important features include good functional group tolerance, operational simplicity, gram-scale synthesis, and broad synthetic utility.