Enantioconvergent Synthesis of Functionalized γ-Butyrolactones via (3 + 2)-Annulation
نویسندگان
چکیده
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.
منابع مشابه
Correction to “Enantioconvergent Synthesis of Functionalized γ-Butyrolactones via (3 + 2)-Annulation”
Supporting Information. Some of the catalyst identifiers (A−G) used in the Supporting Information did not match those shown in the Communication. We have updated the Supporting Information to eliminate this discrepancy. Prof. D. E. Ward (University of Saskatchewan) alerted us to several relevant publications involving enantioconvergent proline-catalyzed aldol reactions of chiral racemic electro...
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عنوان ژورنال:
دوره 137 شماره
صفحات -
تاریخ انتشار 2015