Allylic Alkylation of Cyclic Vinylogous Esters and Thioesters

Significance

Here the Trost group has further expanded their asymmetric allylic alkylation strategy to include vinylogous thioester substrates. The products arising from this reaction contain very useful functionalities for further elaboration. Two types of substrates were synthesized and tested. The synthesis of enol carbonates 1 is shown and interestingly, in an effort to form analogues with alkoxy groups (not sulfides) under similar reaction conditions, the reaction did not proceed as smoothly. These substrates were then subjected to palladium catalysis and afforded the desired products with very high ee values. β-Keto esters were also viable substrates for this reaction.