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Intramolecular C(sp³ )-H Bond Oxygenation by Transition-Metal Acylnitrenoids.

ABSTRACT: This study demonstrates for the first time that easily accessible transition-metal acylnitrenoids can be used for controlled direct C(sp³ )-H oxygenations. Specifically, a ruthenium catalyst activates N-benzoyloxycarbamates as nitrene precursors towards regioselective intramolecular C-H oxygenations to provide cyclic carbonates, hydroxylated carbamates, or 1,2-diols. The method can be applied to the chemoselective C-H oxygenation of benzylic, allylic, and propargylic C(sp³ )-H bonds. The reaction can be performed in an enantioselective fashion and switched in a catalyst-controlled fashion between C-H oxygenation and C-H amination. This work provides a new reaction mode for the regiocontrolled and stereocontrolled conversion of C(sp³ )-H into C(sp³ )-O bonds.

SUBMITTER: Tan Y

PROVIDER: S-EPMC7756817 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Intramolecular C(sp3 )-H Bond Oxygenation by Transition-Metal Acylnitrenoids.

Tan Yuqi Y Chen Shuming S Zhou Zijun Z Hong Yubiao Y Ivlev Sergei S Houk K N KN Meggers Eric E

Angewandte Chemie (International ed. in English) 20200924 48

This study demonstrates for the first time that easily accessible transition-metal acylnitrenoids can be used for controlled direct C(sp3 )-H oxygenations. Specifically, a ruthenium catalyst activates N-benzoyloxycarbamates as nitrene precursors towards regioselective intramolecular C-H oxygenations to provide cyclic carbonates, hydroxylated carbamates, or 1,2-diols. The method can be applied to the chemoselective C-H oxygenation of benzylic, allylic, and propargylic C(sp3 ...[more]

PMID: 32729945

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