Iodobenzene-Mediated Intramolecular Oxidative Coupling of Substituted 4-Hydroxyphenyl-N-phenylbenzamides for the Synthesis of Spirooxindoles

Phenyliodine(III) bis(trifluoroacetate) (PIFA) can effect the intramolecular oxidative coupling of substituted 4-hydroxyphenyl-N-phenylbenzamides. The transformations could be realized in a catalytic manner by using iodobenzene as catalyst and m-chloroperoxybenzoic acid or urea center dot H2O2 as terminal oxidant. This reaction constitutes an efficient method for the synthesis of spirooxindoles.