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Towards an asymmetric β-selective addition of azlactones to allenoates.

ABSTRACT: We herein report the asymmetric organocatalytic addition of azlactones to allenoates. Upon using chiral quaternary ammonium salt catalysts, i.e., Maruoka's binaphthyl-based spirocyclic ammonium salts, the addition of various azlactones to allenoates proceeds in a β-selective manner with moderate levels of enantioselectivities (up to 83:17 er). Furthermore, the obtained products can be successfully engaged in nucleophilic ring opening reactions, thus giving highly functionalized α-amino acid derivatives.

SUBMITTER: Nasiri B

PROVIDER: S-EPMC11228823 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature

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Towards an asymmetric β-selective addition of azlactones to allenoates.

Nasiri Behzad B Pasdar Ghaffar G Zebrowski Paul P Röser Katharina K Naderer David D Waser Mario M

Beilstein journal of organic chemistry 20240704

We herein report the asymmetric organocatalytic addition of azlactones to allenoates. Upon using chiral quaternary ammonium salt catalysts, i.e., Maruoka's binaphthyl-based spirocyclic ammonium salts, the addition of various azlactones to allenoates proceeds in a β-selective manner with moderate levels of enantioselectivities (up to 83:17 er). Furthermore, the obtained products can be successfully engaged in nucleophilic ring opening reactions, thus giving highly functionalized α-amino acid deri ...[more]

PMID: 38978748

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