Cooperative NHC/Photoredox Catalyzed Ring‐Opening of Aryl Cyclopropanes to 1‐Aroyloxylated‐3‐Acylated Alkanes. (25th October 2021)

• Record Type: Journal Article
• Authors: Zuo, Zhijun; Daniliuc, Constantin G.; Studer, Armido
• Is Part Of: Angewandte Chemie. Volume 133:Number 48(2021)
• Page Start: 25456
• Page End: 25461
• Publication Date: 2021-10-25
• Subjects: cascade reactions -- cyclopropanes -- N-heterocyclic carbenes -- photoredox catalysis -- reaction mechanisms; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202110304
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Cyclopropanes are an important class of building blocks in organic synthesis. Herein, a ring‐opening/arylcarboxylation/acylation cascade reaction for the 1, 3‐difunctionalization of aryl cyclopropanes enabled by cooperative NHC and organophotoredox catalysis is reported. The cascade works on monosubstituted cyclopropanes that are in contrast to the heavily investigated donor–acceptor cyclopropanes more challenging to be difunctionalized. The key step is a radical/radical cross coupling of a benzylic radical generated in the photoredox catalysis cycle with a ketyl radical from the NHC catalysis cycle. The transformation features metal‐free reaction conditions and tolerates a diverse range of functionalities. Abstract : Ring‐opening/arylcarboxylation/acylation of mono, di and trisubstituted cyclopropanes enabled by cooperative NHC and organophotoredox catalysis for the preparation of γ‐aroyloxy ketones is reported. Key step is the radical/radical cross‐coupling of a benzylic radical generated in the photoredox catalysis cycle and a ketyl radical formed in the NHC catalysis cycle.