Enantioconvergent Synthesis of Functionalized γ-Butyrolactones via (3 + 2)-Annulation
作者:C. Guy Goodman、Morgan M. Walker、Jeffrey S. Johnson
DOI:10.1021/ja511701j
日期:2015.1.14
A dynamic kineticresolution of β-halo α-keto esters in an asymmetric homoenolate reaction is described. A chiral N-hetereocyclic carbene catalyzes the a3 → d3-umpolung addition of α,β-enals to racemic α-keto esters, forming γ-butyrolactones with threecontiguousstereocenters. The addition occurs with high regio-, diastereo-, and enantiocontrol. This methodology constitutes an intermolecular DKR process