Metalla‐Claisen Rearrangement in Gold‐Catalyzed [4+2] Reaction: A New Elementary Reaction Suggested for Future Reaction Design

Abstract

AbstractWe report here computational evidence for a metalla‐Claisen rearrangement (MCR) in the case of gold‐catalyzed [4+2] cycloaddition reaction of yne‐dienes. The [4+2] reaction starts from exo cyclopropanation, followed by MCR and reductive elimination. The cyclopropane moiety formed in the first step is crucial for a low barrier of the MCR step. In addition, the importance of an appropriate combination of the tether group and the terminal substituent on alkyne in the yne‐diene substrates was studied. The mechanism of rhodium‐catalyzed [4+2] reaction of yne‐dienes was also investigated to see whether an MCR mechanism is involved or not. The findings and new understanding hereby reported represent an important advance in the catalysis field.