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N-Heterocyclic Carbene Catalyzed Photoenolization/Diels-Alder Reaction of Acid Fluorides.

ABSTRACT: The combination of light activation and N-heterocyclic carbene (NHC) organocatalysis has enabled the use of acid fluorides as substrates in a UVA-light-mediated photochemical transformation previously observed only with aromatic aldehydes and ketones. Stoichiometric studies and TD-DFT calculations support a mechanism involving the photoactivation of an ortho-toluoyl azolium intermediate, which exhibits "ketone-like" photochemical reactivity under UVA irradiation. Using this photo-NHC catalysis approach, a novel photoenolization/Diels-Alder (PEDA) process was developed that leads to diverse isochroman-1-one derivatives.

SUBMITTER: Mavroskoufis A

PROVIDER: S-EPMC7027522 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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N-Heterocyclic Carbene Catalyzed Photoenolization/Diels-Alder Reaction of Acid Fluorides.

Mavroskoufis Andreas A Rajes Keerthana K Golz Paul P Agrawal Arush A Ruß Vincent V Götze Jan P JP Hopkinson Matthew N MN

Angewandte Chemie (International ed. in English) 20200109 8

The combination of light activation and N-heterocyclic carbene (NHC) organocatalysis has enabled the use of acid fluorides as substrates in a UVA-light-mediated photochemical transformation previously observed only with aromatic aldehydes and ketones. Stoichiometric studies and TD-DFT calculations support a mechanism involving the photoactivation of an ortho-toluoyl azolium intermediate, which exhibits "ketone-like" photochemical reactivity under UVA irradiation. Using this photo-NHC catalysis a ...[more]

PMID: 31814280

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