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The Origin of Catalytic Benzylic C-H Oxidation over a Redox-Active Metal-Organic Framework.

ABSTRACT: Selective oxidation of benzylic C-H compounds to ketones is important for the production of a wide range of fine chemicals, and is often achieved using toxic or precious metal catalysts. Herein, we report the efficient oxidation of benzylic C-H groups in a broad range of substrates under mild conditions over a robust metal-organic framework material, MFM-170, incorporating redox-active [Cu₂ ^II (O₂ CR)₄ ] paddlewheel nodes. A comprehensive investigation employing electron paramagnetic resonance (EPR) spectroscopy and synchrotron X-ray diffraction has identified the critical role of the paddlewheel moiety in activating the oxidant ^t BuOOH (tert-butyl hydroperoxide) via partial reduction to [Cu^II Cu^I (O₂ CR)₄ ] species.

SUBMITTER: Kimberley L

PROVIDER: S-EPMC8361671 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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The Origin of Catalytic Benzylic C-H Oxidation over a Redox-Active Metal-Organic Framework.

Kimberley Louis L Sheveleva Alena M AM Li Jiangnan J Carter Joseph H JH Kang Xinchen X Smith Gemma L GL Han Xue X Day Sarah J SJ Tang Chiu C CC Tuna Floriana F McInnes Eric J L EJL Yang Sihai S Schröder Martin M

Angewandte Chemie (International ed. in English) 20210604 28

Selective oxidation of benzylic C-H compounds to ketones is important for the production of a wide range of fine chemicals, and is often achieved using toxic or precious metal catalysts. Herein, we report the efficient oxidation of benzylic C-H groups in a broad range of substrates under mild conditions over a robust metal-organic framework material, MFM-170, incorporating redox-active [Cu2 II (O2 CR)4 ] paddlewheel nodes. A comprehensive investigation ...[more]

PMID: 33848040

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