Andrea Cataffo, Eduardo Garcia-Padilla, Imma Escofet, Nicolás Fincias, Anna Arnanz, Giuseppe Zuccarello, Guilong Tian, Luyu Cai, Fereshteh Khorasani, Feliu Maseras, Antonio M. Echavarren
-chiral 2,5-diarylpyrrolidine unit. Using an achiral catalyst of the same family, the enantioselective cascade cyclization of bromo-1,5-enynes to form polycyclic scaffolds was also accomplished for the first time. Interestingly, performing the cyclization of bromo-1,6-enynes in the absence of an alcohol nucleophile led to the formation of nearly racemic cycloisomerization products. Control experiments and DFT calculations support a mechanism involving an in-cycle racemization process mediated by a 1,2-hydrogen shift, shedding new light on the mechanism of gold(i)-catalyzed alkoxycyclizations.