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A Cooperative Ternary Catalysis System for Asymmetric Lactonizations of ?-Ketoesters.

ABSTRACT: A general and enantioselective N-heterocyclic carbene (NHC)-catalyzed lactonization of simple enals and ?-ketoesters has been discovered using a new ternary cooperative catalytic system. The highly selective annulation was achieved by using a combination of a chiral NHC, a hydrogen-bond donor, and a metal salt, facilitating self-assembly of the reactive partners. A proposed model for this new mode of NHC chiral relay catalysis is supported by experimental and computational mechanistic studies.

SUBMITTER: Murauski KJR

PROVIDER: S-EPMC6251415 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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A Cooperative Ternary Catalysis System for Asymmetric Lactonizations of α-Ketoesters.

Murauski Kathleen J R KJR Walden Daniel M DM Cheong Paul Ha-Yeon PH Scheidt Karl A KA

Advanced synthesis & catalysis 20170814 21

A general and enantioselective <i>N</i>-heterocyclic carbene (NHC)-catalyzed lactonization of simple enals and α-ketoesters has been discovered using a new ternary cooperative catalytic system. The highly selective annulation was achieved by using a combination of a chiral NHC, a hydrogen-bond donor, and a metal salt, facilitating self-assembly of the reactive partners. A proposed model for this new mode of NHC chiral relay catalysis is supported by experimental and computational mechanistic stu ...[more]

PMID: 30473657

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