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Modular Enantioselective Synthesis of cis-Cyclopropanes through Self-Sensitized Stereoselective Photodecarboxylation with Benzothiazolines.

ABSTRACT: Chiral cis-cyclopropanes are strained rigid analogues of alkyl chains, whose study and application are limited by their difficult synthesis. A modular approach from olefin materials is enabled by the discovery of the electron donor-acceptor (EDA) interaction between 2-substituted benzothiazolines and N-hydroxyphthalimide esters. These complexes are activated by visible light without photocatalysts, and the benzothiazoline reagent plays a triple role as a photoreductant, a stereoselective hydrogen-atom donor, and a Brønsted acid. Beyond the enantioselective synthesis of cis-cyclopropanes, these results introduce benzothiazolines as accessible and easily tunable self-sensitized photoreductants.

SUBMITTER: Costantini M

PROVIDER: S-EPMC8576787 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Modular Enantioselective Synthesis of cis-Cyclopropanes through Self-Sensitized Stereoselective Photodecarboxylation with Benzothiazolines.

Costantini Matteo M Mendoza Abraham A

ACS catalysis 20211018 21

Chiral cis-cyclopropanes are strained rigid analogues of alkyl chains, whose study and application are limited by their difficult synthesis. A modular approach from olefin materials is enabled by the discovery of the electron donor-acceptor (EDA) interaction between 2-substituted benzothiazolines and N-hydroxyphthalimide esters. These complexes are activated by visible light without photocatalysts, and the benzothiazoline reagent plays a triple role as a photoreductant, a stereosel ...[more]

PMID: 34765283

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