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

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.

Key words

C–H functionalization - phenylation - photoreaction - aryl ketone - ether - carbamate

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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