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Enantioselective Alkynylation of Unstabilized Cyclic Iminium Ions.

ABSTRACT: An enantioselective copper-catalyzed alkynylation of unstabilized cyclic iminium ions has been developed. Whereas such alkynylations typically utilize pyridinium, quinolinium and isoquinolinium intermediates, this method enables use of cyclic iminium ions unstabilized by resonance. With the use of a Lewis acid and copper catalyst, these iminium ions are generated in situ from readily available hemiaminal methyl ethers and transformed into highly enantioenriched α-alkynylated cyclic amines. A variety of terminal alkynes can be incorporated in high yields and enantiomeric excesses.

SUBMITTER: Guan W

PROVIDER: S-EPMC10769448 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Enantioselective Alkynylation of Unstabilized Cyclic Iminium Ions.

Guan Weiye W Santana Samantha O SO Liao Jennie J Henninger Kelci K Watson Mary P MP

ACS catalysis 20201112 23

An enantioselective copper-catalyzed alkynylation of unstabilized cyclic iminium ions has been developed. Whereas such alkynylations typically utilize pyridinium, quinolinium and isoquinolinium intermediates, this method enables use of cyclic iminium ions unstabilized by resonance. With the use of a Lewis acid and copper catalyst, these iminium ions are generated <i>in situ</i> from readily available hemiaminal methyl ethers and transformed into highly enantioenriched α-alkynylated cyclic amines ...[more]

PMID: 38186925

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