Photoinduced iron-catalyzed reduction of nitroarenes for multicomponent synthesis of α-branched secondary amines
Huiji Gao1, Qian Zhang2, Ke Zheng1
1Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China. kzheng@scu.edu.cn.
Abstract:
Herein, we report a visible-light-induced, iron-catalyzed protocol that achieves in situ reduction of nitroarenes to anilines, followed by alkane C-H activation via a ligand-to-metal charge transfer (LMCT) pathway to furnish α-branched secondary amines under mild conditions. This one-pot, multicomponent strategy tolerates a wide range of nitroarenes, aldehydes, and alkanes, affording the desired products in good to excellent yields with broad functional group compatibility. Mechanistic investigations reveal that visible-light irradiation promotes efficient reduction of nitroarenes, while photoexcitation of Fe(III) species triggers LMCT to generate chlorine radicals, which engage in the subsequent three-component coupling.
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