(Diacyloxyiodo)benzenes-Driven Palladium-Catalyzed Cyclizations of Unsaturated N-Sulfonylamides: Opportunities of Path Selection

A study of the palladium(II)-catalyzed cyclization of unsaturated N-sulfonylamides was undertaken, using (diacyloxyiodo)benzenes as terminal oxidizing agents. Different reactivities were observed as a function of the nature of the unsaturation (terminal vs. internal), or of the hypervalent iodine compound used (diacetoxyiodobenzene vs. bistrifluoroacetoxyiodobenzene). Proper parameter selection allows the direction of the cyclization to be chosen towards either a global aminoacetoxylation, an allylic amination via aminopalladation, or an allylic amination via allylic C-H activation.