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A cooperative N-heterocyclic carbene/chiral phosphate catalysis system for allenolate annulations.

ABSTRACT: The highly enantioselective NHC-catalyzed [3+2] annulation reaction with ?,?-alkynals and ?-ketoesters has been developed. A new mode of cooperative catalysis involving the combination of a chiral Brønsted acid and a C1-symmetric biaryl saturated-imidazolium precatalyst was required to generate the desired ?-crotonolactones in high yields and levels of enantioselectivity.

SUBMITTER: Lee A

PROVIDER: S-EPMC4142640 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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A cooperative N-heterocyclic carbene/chiral phosphate catalysis system for allenolate annulations.

Lee Anna A Scheidt Karl A KA

Angewandte Chemie (International ed. in English) 20140604 29

The highly enantioselective NHC-catalyzed [3+2] annulation reaction with α,β-alkynals and α-ketoesters has been developed. A new mode of cooperative catalysis involving the combination of a chiral Brønsted acid and a C1-symmetric biaryl saturated-imidazolium precatalyst was required to generate the desired γ-crotonolactones in high yields and levels of enantioselectivity. ...[more]

PMID: 24895280

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