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Updated: May 16, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Electrophotocatalysis Enables Birch-Type Dearomative Alkylation
Cheng Wang1,2, Ya-Jing Chen1,2, Wen-Jie Kang1,2
1Key Laboratory of Supramolecular Photochemistry & CAS-HKU Joint Laboratory On New Materials, New Cornerstone Science Laboratory, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, P. R. China.
Abstract:
Birch-type dearomative alkylation of (hetero)arenes is straightforward for constructing skeletons bearing sp3-hybridized carbon centers. However, such a tandem reaction suffers from competitive protonation and intractable alkylation, leading to the formation of 1,4-cyclohexadienes rather than dearomative alkylation in a one-pot reaction. Herein we report the first electrophotocatalytic Birch-type dearomative alkylation of (hetero)arenes. Using N,N-bis(2,6-diisopropylphenyl)perylene-3,4,9,10-bis(dicarboximide) as an electrophotocatalyst and alkyl chlorides as alkylating agents, a range of anthracene, naphthalene and acridine derivatives have been successfully converted into their dearomatively alkylated frameworks. Control experiments, spectroscopic studies and DFT calculations revealed that tetrabutylammonium-stabilized arene radical anions can react with alkyl chlorides under metal-free conditions via "Birch-SN2" or "XAT-SRN1" pathway. The extremely mild reaction conditions, high site selectivity and diverse functional group tolerance, together with the simulated sunlight trials and the utilization of solar electricity, highlight promising potential of this tandem reaction in directly modifying (hetero)arenes with various electrophiles.
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