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DOI: 10.1055/a-2338-4243
Photoinduced Aryl Ketone-Catalyzed Phenylation of C(sp3)–H Bonds Attached to the Heteroatom of Ethers and N-Boc-Amines via Concerted Homolytic Aromatic Substitution
This research was supported by the JSPS KAKENHI Grant Number JP22K05096 to S.K.
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Abstract
A single-step phenylation at the non-acidic C(sp3)–H bond attached to the heteroatom of ethers and N-Boc-amines has been achieved using photoexcited 4-benzoylpyridine as a hydrogen atom transfer (HAT) catalyst. The design of electron-deficient (trifluoromethylsulfonyl)benzene derivatives, as a phenyl precursor, was critical to realizing the present transformation. Moreover, the DFT calculations indicated that the present transformation proceeds via a concerted homolytic aromatic substitution rather than via a stepwise one involving the formation of a cyclohexadienyl radical intermediate.
Supporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/a-2338-4243.
- Supporting Information
Publication History
Received: 01 May 2024
Accepted after revision: 04 June 2024
Accepted Manuscript online:
04 June 2024
Article published online:
02 July 2024
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For representative reviews on homolytic aromatic substitution, see:
For selected examples of the cyclohexadienyl radical detection, see:
For reviews on the homolytic aromatic substitution of heteroaromatics known as the Minisci reaction, see:
For recent examples of C(sp3)–H functionalizations using a photoexcited aryl ketone from our group, see:
For representative reports on C(sp3)–H functionalizations using a photoexcited aryl ketone from other groups, see:
For recent examples of C(sp3)–H arylations using a photoexcited aryl ketone from our group, see:
For closely related reports on C(sp3)–H arylations through homolytic aromatic substitution from other groups, see:
For other recent examples of C(sp3)–H phenylations, see: