Catalytic Oxidative 1,2-Shift in 1,1′-Disubstituted Olefins Using Arene(iodo)sulfonic Acid as the Precatalyst and Oxone as the Oxidant

An efficient, catalytic hypervalent iodine-mediated oxidative 1,2-shift of 1,1′-disubstituted olefins is described. This methodology provides concise access to homobenzylic ketones with electron-donating substituents. In the case of cyclic systems, this transformation results in ring-expanded β-benzocycloalkanones, which are useful for further elaboration.