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Electrocatalytic Activation of Donor-Acceptor Cyclopropanes and Cyclobutanes: An Alternative C(sp³ )-C(sp³ ) Cleavage Mode.

ABSTRACT: We describe the first electrochemical activation of D-A cyclopropanes and D-A cyclobutanes leading after C(sp³ )-C(sp³ ) cleavage to the formation of highly reactive radical cations. This concept is utilized to formally insert molecular oxygen after direct or DDQ-assisted anodic oxidation of the strained carbocycles, delivering β- and γ-hydroxy ketones and 1,2-dioxanes electrocatalytically. Furthermore, insights into the mechanism of the oxidative process, obtained experimentally and by additional quantum-chemical calculations are presented. The synthetic potential of the reaction products is demonstrated by diverse derivatizations.

SUBMITTER: Kolb S

PROVIDER: S-EPMC8362004 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Electrocatalytic Activation of Donor-Acceptor Cyclopropanes and Cyclobutanes: An Alternative C(sp3 )-C(sp3 ) Cleavage Mode.

Kolb Simon S Petzold Martin M Brandt Felix F Jones Peter G PG Jacob Christoph R CR Werz Daniel B DB

Angewandte Chemie (International ed. in English) 20210616 29

We describe the first electrochemical activation of D-A cyclopropanes and D-A cyclobutanes leading after C(sp3 )-C(sp3 ) cleavage to the formation of highly reactive radical cations. This concept is utilized to formally insert molecular oxygen after direct or DDQ-assisted anodic oxidation of the strained carbocycles, delivering β- and γ-hydroxy ketones and 1,2-dioxanes electrocatalytically. Furthermore, insights into the mechanism of the oxidative process, obtained experime ...[more]

PMID: 33890714

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