Synthesis of Spirofurooxindoles via Phenyliodine(III) Bis(trifluoroacetate) (PIFA)‐Mediated Cascade Oxidative C−O and C−C Bond Formation

Upon treatment with solely a hypervalent iodine reagent of phenyliodine(III) bis(trifluoroacetate) (PIFA), 3‐(2‐hydroxyphenyl)‐3‐oxo‐ N ‐phenyl propanamides and a series of its derivatives were conveniently converted to a class of undocumented spirofurooxindoles under mild conditions. Control experiments provided evidence that this spirocyclization process encompassed a cascade oxidative reactions involving the formation of a C−O bond prior to that of C−C bond.