Catalysis of 6π Electrocyclizations

摘要

The synthetic power of pericyclic reactions has greatly increased with the emergence of catalytic variants. Indeed, catalysis in cycloadditions and sigmatropic rearrangements is now well established. General methods for the catalysis of electrocyclizations, however, have remained elusive, with the notable exception of the Nazarov cycliza-tion. The development of such methods would enable electrocyclizations to occur under milder conditions and create the possibility of catalytic asymmetric variants. Herein, we report the first examples of catalytic 6π electrocyclizations and provide a detailed investigation into the mechanism of these reactions.