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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Photochemical C-H Arylation of Napthoquinones Using Eosin Y
Bhawana Nagar1, Basab Bijayi Dhar1
1Department of Chemistry, School of Natural Sciences, Shiv Nadar IoE, Gautam Buddha Nagar, Dadri 201314, Uttar Pradesh, India.
Abstract:
A visible-light-mediated C-H arylation of substituted 1,4-napthoquinones (1,4-SNQ) and 1,2-napthoquinone (1,2-NQ) with diazonium salt using a photocatalyst eosin Y at room temperature in a single step (isolated yield of ≥75%) is described in this report. The rate-determining step of the reaction is aryl radical generation, which was trapped by high-resolution mass spectrometry. Cost-effectiveness, operational simplicity, a short reaction time, high atom economy, and a good yield make this photoredox-mediated process a valuable alternative to the transition-metal (Fe, Cu, Pd, etc.)-catalyzed reaction.
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