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First use of a divalent lanthanide for visible-light-promoted photoredox catalysis.

ABSTRACT: We report the first catalytic use of a divalent lanthanide in visible-light-promoted bond-forming reactions. Our new precatalyst uses europium in the +2 oxidation state and is active in the presence of blue light from light-emitting diodes. The use of low-energy visible light reduces the occurrence of potential side reactions that might be induced by higher-energy UV light. The system described here uses zinc metal as a sacrificial reductant and is tolerant to wet, protic solvents. The catalyst can be made in situ from relatively inexpensive and air-stable EuCl3·6H2O, and the ligand can be synthesized in large quantities in two steps. With 0.5% loading of precatalyst, an average of 120 turnovers was observed in six hours for reductive coupling of benzyl chloride. We expect that the results will initiate the study of visible-light-promoted photoredox catalysis using divalent europium in a variety of reactions.

SUBMITTER: Jenks TC

PROVIDER: S-EPMC5890796 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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First use of a divalent lanthanide for visible-light-promoted photoredox catalysis.

Jenks Tyler C TC Bailey Matthew D MD Hovey Jessica L JL Fernando Shanilke S Basnayake Gihan G Cross Michael E ME Li Wen W Allen Matthew J MJ

Chemical science 20171221 5

We report the first catalytic use of a divalent lanthanide in visible-light-promoted bond-forming reactions. Our new precatalyst uses europium in the +2 oxidation state and is active in the presence of blue light from light-emitting diodes. The use of low-energy visible light reduces the occurrence of potential side reactions that might be induced by higher-energy UV light. The system described here uses zinc metal as a sacrificial reductant and is tolerant to wet, protic solvents. The catalyst ...[more]

PMID: 29675173

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