Synthesis of (<i>E</i>)-3-(Isobenzofuran-3(1<i>H</i>)-ylidene)indolin-2-ones by the Palladium-Catalyzed Intramolecular C−H Functionalization Process

A novel and selective protocol has been developed for the synthesis of (E)-3-(isobenzofuran-3(1H)-ylidene)indolin-2-ones by Pd-catalyzed oxidative intramolecular C−H functionalization reactions of various 3-(2-(hydroxymethyl)aryl)-N-methyl-N-arylpropiolamides in moderate yields. Mechanisms involving a C−H activation process were proposed for this transformation on the basis of the observed values of kinetic isotope effects.