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Ruthenium catalyzed β-selective alkylation of vinylpyridines with aldehydes/ketones via N₂H₄ mediated deoxygenative couplings.

ABSTRACT: Umpolung (polarity reversal) tactics of aldehydes/ketones have greatly broadened carbonyl chemistry by enabling transformations with electrophilic reagents and deoxygenative functionalizations. Herein, we report the first ruthenium-catalyzed β-selective alkylation of vinylpyridines with both naturally abundant aromatic and aliphatic aldehyde/ketones via N₂H₄ mediated deoxygenative couplings. Compared with one-electron umpolung of carbonyls to alcohols, this two-electron umpolung strategy realized reductive deoxygenation targets, which were not only applicable to the regioselective alkylation of a broad range of 2/4-alkene substituted pyridines, but also amenable to challenging 3-vinyl and steric-embedded internal pyridines as well as their analogous heterocyclic structures.

SUBMITTER: Lv L

PROVIDER: S-EPMC8179402 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Ruthenium catalyzed β-selective alkylation of vinylpyridines with aldehydes/ketones via N2H4 mediated deoxygenative couplings.

Lv Leiyang L Li Chao-Jun CJ

Chemical science 20201230 8

Umpolung (polarity reversal) tactics of aldehydes/ketones have greatly broadened carbonyl chemistry by enabling transformations with electrophilic reagents and deoxygenative functionalizations. Herein, we report the first ruthenium-catalyzed β-selective alkylation of vinylpyridines with both naturally abundant aromatic and aliphatic aldehyde/ketones via N2H4 mediated deoxygenative couplings. Compared with one-electron umpolung of carbonyls to alcohols, this two-elect ...[more]

PMID: 34164052

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