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Enantioselective propargylic [1,3]-rearrangements: copper-catalyzed O-to-N migrations toward C-N bond formation.

ABSTRACT: We have identified an enantioselective copper-catalyzed O-to-N formal [1,3]-rearrangement to form N-propargylic-2-pyridones. This enantioconvergent O-to-N propargylic rearrangement occurs rapidly at ambient temperature and high enantioselectivity is observed for a range of 3-alkyl-substituted substrates. Stereochemical features include a mild kinetic enantioenrichment of the substrate and a non-linear relationship between product and ligand enantiopurity. Based on kinetic analyses and cross-over experiments, we put forward a mechanistic proposal involving Cu-acetylides as well as bimetallic intermediates in which coordination to the pyridyl nitrogen is likely a crucial binding interaction.

SUBMITTER: Cheng LJ

PROVIDER: S-EPMC5635726 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Enantioselective propargylic [1,3]-rearrangements: copper-catalyzed O-to-N migrations toward C-N bond formation.

Cheng Li-Jie LJ Brown Alexander P N APN Cordier Christopher J CJ

Chemical science 20170331 6

We have identified an enantioselective copper-catalyzed O-to-N formal [1,3]-rearrangement to form N-propargylic-2-pyridones. This enantioconvergent O-to-N propargylic rearrangement occurs rapidly at ambient temperature and high enantioselectivity is observed for a range of 3-alkyl-substituted substrates. Stereochemical features include a mild kinetic enantioenrichment of the substrate and a non-linear relationship between product and ligand enantiopurity. Based ...[more]

PMID: 29081964

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