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Isothiourea-Catalyzed [2 + 2] Cycloaddition of C(1)-Ammonium Enolates and N-Alkyl Isatins.

ABSTRACT: Enantioselective [2 + 2] cycloaddition of C(1)-ammonium enolates generated catalytically using the isothiourea HyperBTM with N-alkyl isatins gives spirocyclic β-lactones. In situ ring opening with an amine nucleophile generates isolable highly enantioenriched products in up to 92:8 dr and in >99:1 er.

SUBMITTER: Abdelhamid Y

PROVIDER: S-EPMC9490795 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Isothiourea-Catalyzed [2 + 2] Cycloaddition of C(1)-Ammonium Enolates and N-Alkyl Isatins.

Abdelhamid Yusra Y Kasten Kevin K Dunne Joanne J Hartley Will C WC Young Claire M CM Cordes David B DB Slawin Alexandra M Z AMZ Ng Sean S Smith Andrew D AD

Organic letters 20220718 29

Enantioselective [2 + 2] cycloaddition of C(1)-ammonium enolates generated catalytically using the isothiourea HyperBTM with N-alkyl isatins gives spirocyclic β-lactones. In situ ring opening with an amine nucleophile generates isolable highly enantioenriched products in up to 92:8 dr and in >99:1 er. ...[more]

PMID: 35848722

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