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The Catalytic Asymmetric Intermolecular Prins Reaction.

ABSTRACT: Despite their significant potential, catalytic asymmetric reactions of olefins with formaldehyde are rare and metal-free approaches have not been previously disclosed. Here we describe an enantioselective intermolecular Prins reaction of styrenes and paraformaldehyde to form 1,3-dioxanes, using confined imino-imidodiphosphate (iIDP) Brønsted acid catalysts. Isotope labeling experiments and computations suggest a concerted, highly asynchronous addition of an acid-activated formaldehyde oligomer to the olefin. The enantioenriched 1,3-dioxanes can be transformed into the corresponding optically active 1,3-diols, which are valuable synthetic building blocks.

SUBMITTER: Diaz-Oviedo CD

PROVIDER: S-EPMC8679094 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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The Catalytic Asymmetric Intermolecular Prins Reaction.

Díaz-Oviedo C David CD Maji Rajat R List Benjamin B

Journal of the American Chemical Society 20211130 49

Despite their significant potential, catalytic asymmetric reactions of olefins with formaldehyde are rare and metal-free approaches have not been previously disclosed. Here we describe an enantioselective intermolecular Prins reaction of styrenes and paraformaldehyde to form 1,3-dioxanes, using confined imino-imidodiphosphate (<i>i</i>IDP) Brønsted acid catalysts. Isotope labeling experiments and computations suggest a concerted, highly asynchronous addition of an acid-activated formaldehyde oli ...[more]

PMID: 34846874

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