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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
A natural light induced regioselective 6pi-electrocyclisation-oxidative aromatisation reaction: experimental and
Benjamin E Moulton1, Hao Dong, Ciara T O'Brien
1Department of Chemistry, University of York, Heslington, York, UK.
Abstract:
Stoichiometric intermolecular Pauson-Khand reactions of 4-(phenylethynyl)-6-methyl-2-pyrones with norbornene and dicobalt(0)octacarbonyl provide cyclopentenone products that undergo a facile 6pi-electrocyclisation-oxidative aromatisation transformation in the presence of natural light and oxygen, affording functionalised benzo[h]indeno[1,2-f]isochromene type products. The results are rationalised by theoretical studies, which confirm that the electrocyclisation process is favoured at C3 in the 2-pyrone ring system. The identity and precise arrangement of the 'trienyl' substituents control whether the electrocyclisation occurs in natural light.
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