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Desymmetrization of meso-Dibromocycloalkenes through Copper(I)-Catalyzed Asymmetric Allylic Substitution with Organolithium Reagents.

ABSTRACT: The highly regio- and enantioselective (up to >99:1 dr, up to 99:1 er) desymmetrization of meso-1,4-dibromocycloalk-2-enes using asymmetric allylic substitution with organolithium reagents to afford enantioenriched bromocycloalkenes (ring size of 5 to 7) has been achieved. The cycloheptene products undergo an unusual ring contraction. The synthetic versatility of this Cu(I)-catalyzed reaction is demonstrated by the concise stereocontrolled preparation of cyclic amino alcohols, which are privileged chiral structures in natural products and pharmaceuticals and widely used in synthesis and catalysis.

SUBMITTER: Goh SS

PROVIDER: S-EPMC6002767 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Desymmetrization of meso-Dibromocycloalkenes through Copper(I)-Catalyzed Asymmetric Allylic Substitution with Organolithium Reagents.

Goh Shermin S SS Guduguntla Sureshbabu S Kikuchi Takashi T Lutz Martin M Otten Edwin E Fujita Makoto M Feringa Ben L BL

Journal of the American Chemical Society 20180531 23

The highly regio- and enantioselective (up to >99:1 dr, up to 99:1 er) desymmetrization of meso-1,4-dibromocycloalk-2-enes using asymmetric allylic substitution with organolithium reagents to afford enantioenriched bromocycloalkenes (ring size of 5 to 7) has been achieved. The cycloheptene products undergo an unusual ring contraction. The synthetic versatility of this Cu(I)-catalyzed reaction is demonstrated by the concise stereocontrolled preparation of cyclic amino alcohols, which are privileg ...[more]

PMID: 29790736

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