title: Enantioconvergent synthesis of functionalized γ-butyrolactones via (3 + 2)-annulation.
abstract: A dynamic kinetic resolution of β-halo α-keto esters in an asymmetric homoenolate reaction is described. A chiral N-hetereocyclic carbene catalyzes the a(3) → d(3)-umpolung addition of α,β-enals to racemic α-keto esters, forming γ-butyrolactones with three contiguous stereocenters. The addition occurs with high regio-, diastereo-, and enantiocontrol. This methodology constitutes an intermolecular DKR process to set three stereocenters during the key bond forming event.
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: C Guy
authors.initials: CG
authors.lastname: Goodman
authors.forename: Morgan M
authors.initials: MM
authors.lastname: Walker
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Johnson
mesh_terms: D015107:4-Butyrolactone / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D006571:Heterocyclic Compounds / Q000737:chemistry; D008697:Methane / Q000031:analogs & derivatives / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D006571:Heterocyclic Compounds; C030011:carbene; D015107:4-Butyrolactone; D008697:Methane