Enantioselective Pd-Catalyzed Decarboxylative Allylic Alkylation of Thiopyranones. Access to Acyclic, Stereogenic α‑Quaternary Ketones
journal contributionposted on 2017-09-13, 13:51 authored by Eric J. Alexy, Scott C. Virgil, Michael D. Bartberger, Brian M. Stoltz
A catalytic, enantioselective decarboxylative allylic alkylation of 4-thiopyranones is reported. The α-quaternary 4-thiopyranones produced are challenging to access by standard enolate alkylation owing to facile ring-opening β-sulfur elimination. In addition, reduction of the carbon–sulfur bonds provides access to elusive acyclic α-quaternary ketones. The alkylated products are obtained in up to 92% yield and 94% enantiomeric excess.
alkylated productsAccessenantioselective decarboxylative allylic alkylation4- thiopyranonesaccessThiopyranoneenantiomericacyclic α- quaternary ketonesα- quaternary 4- thiopyranonesKetonering-opening β- sulfur eliminationQuaternaryAcyclicEnantioselective Pd-Catalyzed Decarboxylative Allylic AlkylationStereogenicenolate alkylationbond