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Photochemical C-H Arylation of Napthoquinones Using Eosin Y.

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.

SUBMITTER: Nagar B

PROVIDER: S-EPMC9475624 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Photochemical C-H Arylation of Napthoquinones Using Eosin Y.

Nagar Bhawana B Dhar Basab Bijayi BB

ACS omega 20220831 36

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 ma ...[more]

PMID: 36119980

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