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Merging Asymmetric [1,2]-Additions of Lithium Acetylides to Carbonyls with Type II Anion Relay Chemistry.

ABSTRACT: An enantioselective three-component coupling reaction has been developed, enabling the union of a variety of lithium acetylides and electrophiles exploiting an achiral linchpin via an anionic reaction cascade. This Type II Anion Relay Chemistry tactic is initiated via an enantioselective [1,2]-carbonyl addition exploiting BINOL catalysis to access an enantioenriched alkoxide intermediate. Migration of charge across the linchpin via a [1,4]-Brook rearrangement with electrophile capture affords a three-component propargyl ether adduct. Herein, we report the development, scope, and limitations of this reaction sequence.

SUBMITTER: O'Brien KT

PROVIDER: S-EPMC7307215 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Merging Asymmetric [1,2]-Additions of Lithium Acetylides to Carbonyls with Type II Anion Relay Chemistry.

O'Brien Kevin T KT Smith Amos B AB

Organic letters 20190909 18

An enantioselective three-component coupling reaction has been developed, enabling the union of a variety of lithium acetylides and electrophiles exploiting an achiral linchpin via an anionic reaction cascade. This Type II Anion Relay Chemistry tactic is initiated via an enantioselective [1,2]-carbonyl addition exploiting BINOL catalysis to access an enantioenriched alkoxide intermediate. Migration of charge across the linchpin via a [1,4]-Brook rearrangement with electrophile capture affords a ...[more]

PMID: 31498641

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