Photoredox-Catalyzed Radical Hydroalkylation of Azobenzenes with Alkylboronic Acids
Jiangjiang Li1, Hongyan Zhou1, Shouying Mei1
1College of Science, Gansu Agricultural University, Lanzhou 730070, China.
Abstract:
The facile synthesis of N-alkyl-N,N'-diarylhydrazines has been a long-standing challenge. Here, we report a photoredox-catalyzed hydroalkylation of azobenzenes with alkylboronic acids, which successfully affords diverse N-alkyl-N,N'-diarylhydrazines. With an acridinium salt as the photocatalyst and upon visible light irradiation, a broad range of azobenzenes and alkylboronic acids reacted smoothly in the presence of a Lewis base at ambient temperature. Mechanistic studies revealed that the reaction proceeds via the generation of alkyl radicals and is facilitated by photoredox catalysis.
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