Palladium-Catalyzed Allylic Alkylation via Photocatalytic Nucleophile Generation

The rapid assembly of an easily accessible terminal alkene, an aliphatic C(sp(3))-H coupling partner, and allyl carbonate has been established by merging hydrogen atom transfer photocatalyst-mediated nucleophile generation and palladium-catalyzed allylic alkylation. The synthetic utility of this strategy is embodied by a concise synthesis of (+/-)-mesembrine. Mechanistic studies suggest that this protocol proceeds via a radical/ionic relay process, and a carbanionic species serves as a key intermediate for nucleophile attack on pi-allylpalladium through a classic two-electron allylation pathway. This protocol showcases an atom-economic and environmentally friendly method to generate a nonstabilized nucleophile for transition-metal catalysis.

Automated summary

A rapid synthetic method for a target compound has been developed by combining photocatalysis and palladium catalysis, demonstrating an atom-economic and environmentally friendly strategy. Experimental results suggest that this method has high synthetic utility.