Organophotoredox 1,6-Addition of 3,4-Dihydroquinoxalin-2-ones to para-Quinone Methides Using Visible Light

ACS Organic & Inorganic Au, Journal Year: 2023, Volume and Issue: 3(3), P. 130 - 135

Published: Jan. 20, 2023

An organophotoredox 1,6-radical addition of 3,4-dihidroquinoxalin-2-ones to para-quinone methides catalyzed by Fukuzumi's photocatalyst is described under the irradiation a HP Single LED (455 nm). The corresponding 1,1-diaryl compounds bearing dihydroquinoxalin-2-one moiety (20 examples) are obtained with good excellent yields mild reaction conditions. Several experiments have been carried out in order propose mechanism.

Language: Английский

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Metal-Free Addition of Alkyl Bromides to Access 3,3-Disubstituted Quinoxalinones Enabled by Visible-Light Photoredox Catalysis

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(16), P. 11762 - 11766

Published: Aug. 9, 2023

A metal-free addition of unactivated alkyl bromides to quinoxalin-2(1H)-ones is described. This method enables the construction valuable 3,3-disubstituted dihydroquinoxalin-2(1H)-ones bearing quaternary carbon centers under mild, visible-light photoredox catalysis. High functional group tolerance observed in both quinoxalinone and bromide partners. The ability scale up this was demonstrated photo-flow conditions enable gram-scale synthesis.

Language: Английский

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Facile Entry to Pharmaceutically Important 3-Difluoromethyl-quinoxalin-2-ones Enabled by Visible-Light-Driven Difluoromethylation of Quinoxalin-2-ones

Pharmaceuticals, Journal Year: 2022, Volume and Issue: 15(12), P. 1552 - 1552

Published: Dec. 13, 2022

CF2H moiety has a significant potential utility in drug design and discovery, the incorporation of into biologically active molecules represents an important efficient strategy for seeking lead compounds candidates. On other hand, quinoxalin-2-one is great interest to pharmaceutical chemists as common skeleton frequently occurring plenty natural products bioactive compounds. Herein, we reported practical protocol synthesis 3-CF2H-quinoxalin-2-ones. Thus, presence 3 mol% photocatalyst S-(difluoromethyl)sulfonium salt difluoromethyl radical sources, wide range quinoxalin-2-ones readily underwent visible-light redox-catalyzed difluoromethylation reaction, deliver structurally diverse 3-difluoromethyl-quinoxalin-2-ones. We believe that this would facilitate increasing chances possibilities candidates further boost development fluorine-containing pharmaceuticals.

Language: Английский

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Visible-Light-Induced Metal- and Photosensitizer-Free C(sp³)–H Phosphorylation of 3,4-Dihydroquinoxalin-2(1H)-ones with Diphenylphosphine Oxide

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(16), P. 11659 - 11664

Published: Aug. 1, 2024

Herein, we report a direct phosphorylation of the C(sp3)–H bond 3,4-dihydroquinoxalin-2(1H)-ones using oxygen as green oxidant under visible light at room temperature. This transformation was readily accomplished in absence metal and photosensitizer to construct new C(sp3)–P bonds provide series phosphonylated dihydroquinoxalin-2-ones good excellent yields. approach opens straightforward environmentally friendly access 3-phosphoryl quinoxalin-2-ones derivatives.

Language: Английский

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Highly efficient synthesis of C3-heteroaryl 3-fluorooxindoles via a one-pot stepwise Ce(iii)/photoassisted cross-dehydrogenative coupling/fluorooxidation process

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 10(3), P. 668 - 674

Published: Dec. 19, 2022

A one-pot stepwise strategy has been developed to afford C3-heteroaryl 3-fluorooxindoles via a Ce( iii )/photoassisted cross-dehydrogenative coupling/fluorooxidation process in moderate-to-good yields with excellent functional group compatibility.

Language: Английский

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