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Combined Photoredox and Iron Catalysis for the Cyclotrimerization of Alkynes.

ABSTRACT: Successful combinations of visible-light photocatalysis with metal catalysis have recently enabled the development of hitherto unknown chemical reactions. Dual mechanisms from merging metal-free photocatalysts and earth-abundant metal catalysts are still in their infancy. We report a photo-organo-iron-catalyzed cyclotrimerization of alkynes by photoredox activation of a ligand-free Fe catalyst. The reaction operates under very mild conditions (visible light, 20?°C, 1?h) with 1-2?mol?% loading of the three catalysts (dye, amine, FeCl2 ).

SUBMITTER: Neumeier M

PROVIDER: S-EPMC7496134 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Combined Photoredox and Iron Catalysis for the Cyclotrimerization of Alkynes.

Neumeier Michael M Chakraborty Uttam U Schaarschmidt Dieter D de la Pena O'Shea Victor V Perez-Ruiz Raul R Jacobi von Wangelin Axel A

Angewandte Chemie (International ed. in English) 20200527 32

Successful combinations of visible-light photocatalysis with metal catalysis have recently enabled the development of hitherto unknown chemical reactions. Dual mechanisms from merging metal-free photocatalysts and earth-abundant metal catalysts are still in their infancy. We report a photo-organo-iron-catalyzed cyclotrimerization of alkynes by photoredox activation of a ligand-free Fe catalyst. The reaction operates under very mild conditions (visible light, 20 °C, 1 h) with 1-2 mol % loading of ...[more]

PMID: 32190960

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