Efficient Synthesis of Benzospirocyclohexadienones via PIFA-Promoted Intramolecular Dearomative Spiroannulation

Abstract A rapid and convenient method for the synthesis of differently substituted spiro[cyclohexane-1,1′-isochromane]-2,5-dien-4-one derivatives via phenyliodine(III) bis(trifluoroacetate) (PIFA)-promoted intramolecular oxidative dearomatization at the para position is disclosed, with the aim of building a library of new spirocyclohexadienone scaffolds. Subsequently, this strategy is modified to access novel cyclohexanedienone-containing polycyclic compounds.