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Ruthenium-catalyzed umpolung carboxylation of hydrazones with CO₂.

ABSTRACT: The first ruthenium-catalyzed umpolung carboxylation of hydrazones with CO₂ to generate important aryl acetic acids is reported. Besides aldehyde hydrazones, a variety of ketone hydrazones, which have not been successfully applied in previous umpolung reactions with other reactive electrophiles, also show high reactivity and selectivity under mild conditions. Moreover, this operationally simple protocol features good functional group tolerance, is readily scalable, and offers easy derivation of important structures, including bioactive felbinac and adiphenine. Computational studies reveal that this umpolung reaction proceeds through the generation of a Ru-nitrenoid followed by concerted [4 + 2] cycloaddition with CO₂.

SUBMITTER: Yan SS

PROVIDER: S-EPMC5982211 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2.

Yan Si-Shun SS Zhu Lei L Zhu Lei L Ye Jian-Heng JH Zhang Zhen Z Huang He H Zeng Huiying H Li Chao-Jun CJ Lan Yu Y Yu Da-Gang DG

Chemical science 20180430 21

The first ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2 to generate important aryl acetic acids is reported. Besides aldehyde hydrazones, a variety of ketone hydrazones, which have not been successfully applied in previous umpolung reactions with other reactive electrophiles, also show high reactivity and selectivity under mild conditions. Moreover, this operationally simple protocol features good functional group tolerance, is readily scalable, and offers easy der ...[more]

PMID: 29910940

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