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Construction 7-membered ring via Ni-Al bimetal-enabled C-H cyclization for synthesis of tricyclic imidazoles.

ABSTRACT: The construction of 7-membered ring via direct C7-H cyclization of benzoimidazoles with alkenes would provide a more atom- and step-economical route to tricyclic imidazoles and derivatives that widely exist in a broad range of bioactive molecules. However, transition metal-catalyzed C-H cyclization for medium-ring synthesis has been limited to reactive C-H bonds, instead, the activation of unreactive C-H bonds towards medium synthesis still remains an elusive challenge. Herein, we report a direct construction of 7-membered rings via Ni-Al co-catalyzed unreactive C7-H cyclization of benzoimidazoles with alkenes, providing a series of tricyclic imidazoles in 40-98% yield and with up to 95:5 er.

SUBMITTER: Li JF

PROVIDER: S-EPMC8144396 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Construction 7-membered ring via Ni-Al bimetal-enabled C-H cyclization for synthesis of tricyclic imidazoles.

Li Jiang-Fei JF Xu Wei-Wei WW Wang Rong-Hua RH Li Yue Y Yin Ge G Ye Mengchun M

Nature communications 20210524 1

The construction of 7-membered ring via direct C7-H cyclization of benzoimidazoles with alkenes would provide a more atom- and step-economical route to tricyclic imidazoles and derivatives that widely exist in a broad range of bioactive molecules. However, transition metal-catalyzed C-H cyclization for medium-ring synthesis has been limited to reactive C-H bonds, instead, the activation of unreactive C-H bonds towards medium synthesis still remains an elusive challenge. Herein, we report a direc ...[more]

PMID: 34031420

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