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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Gold-Catalyzed Photoredox C(sp(2)) Cyclization: Formal Synthesis of (±)-Triptolide
Alexandre Cannillo1, Travis R Schwantje1, Maxime Bégin1
1Centre for Catalysis, Research and Innovation, Department of Chemistry and Biomolecular Science, University of Ottawa , 10 Marie Curie, Ottawa, Canada K1N 6N5.
Abstract:
Photoexcitation of a dimeric gold complex showed the activation of a C(sp(2))-Br bond to generate a vinyl radical in a mild photoredox catalysis process. Use of [Au2(dppm)2]Cl2 with 365 nm LEDs in a photoredox catalysis process to produce polycyclic scaffolds using vinyl radicals is reported. This method achieved the synthesis of a small library of butenolide polycyclic compounds and naphthol polycyclic compounds. The efficacy of this photoredox process was further demonstrated by accomplishing the concise formal synthesis of (±)-triptolide.
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