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Catalytic, Enantioselective ?-Alkylation of Azlactones with Nonconjugated Alkenes by Directed Nucleopalladation.

ABSTRACT: A palladium(II)-catalyzed enantioselective ?-alkylation of azlactones with nonconjugated alkenes is described. The reaction employs a chiral BINOL-derived phosphoric acid as the source of stereoinduction, and a cleavable bidentate directing group appended to the alkene to control the regioselectivity and stabilize the nucleopalladated alkylpalladium(II) intermediate in the catalytic cycle. A wide range of azlactones were found to be compatible under the optimal reaction conditions to afford products bearing ?,?-disubstituted ?-amino-acid derivatives with high yields and high enantioselectivity.

SUBMITTER: Nimmagadda SK

PROVIDER: S-EPMC6595491 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Catalytic, Enantioselective α-Alkylation of Azlactones with Nonconjugated Alkenes by Directed Nucleopalladation.

Nimmagadda Sri Krishna SK Liu Mingyu M Karunananda Malkanthi K MK Gao De-Wei DW Apolinar Omar O Chen Jason S JS Liu Peng P Engle Keary M KM

Angewandte Chemie (International ed. in English) 20190227 12

A palladium(II)-catalyzed enantioselective α-alkylation of azlactones with nonconjugated alkenes is described. The reaction employs a chiral BINOL-derived phosphoric acid as the source of stereoinduction, and a cleavable bidentate directing group appended to the alkene to control the regioselectivity and stabilize the nucleopalladated alkylpalladium(II) intermediate in the catalytic cycle. A wide range of azlactones were found to be compatible under the optimal reaction conditions to afford prod ...[more]

PMID: 30729619

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