Development and Mechanistic Studies of Oxidative Prins-Semipinacol Cyclization Reactions

This work shows that allylic alcohols or silyl ethers promote hydride abstraction leading to direct carbon-carbon bond formation or carbon-oxygen bond formation followed by rearrangement, providing the stereoselective construction of spirocyclic ethers through a Prins-semipinacol pathway. A kinetic isotope effect study showed that hydride abstraction is the rate-determining step, consistent with the presence of a distal nucleophilic group lowering the transition state free energy of the oxidation step.