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An Expedient Method for the Umpolung Coupling of Enols with Heteronucleophiles.

ABSTRACT: In this paper, we present an unprecedented and general umpolung protocol that allows the functionalization of silyl enol ethers and of 1,3-dicarbonyl compounds with a large range of heteroatom nucleophiles, including carboxylic acids, alcohols, primary and secondary amines, azide, thiols, and also anionic carbamates derived from CO₂ . The scope of the reaction also extends to carbon-based nucleophiles. The reaction relies on the use of 1-bromo-3,3-dimethyl-1,3-dihydro-1λ³ [d][1,2]iodaoxole, which provides a key α-brominated carbonyl intermediate. The reaction mechanism has been studied experimentally and by DFT, and we propose formation of an unusual enolonium intermediate with a halogen-bonded bromide.

SUBMITTER: Garcia-Vazquez V

PROVIDER: S-EPMC9400875 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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An Expedient Method for the Umpolung Coupling of Enols with Heteronucleophiles.

García-Vázquez Víctor V Carretero Cerdán Alba A Sanz-Marco Amparo A Gómez-Bengoa Enrique E Martín-Matute Belén B

Chemistry (Weinheim an der Bergstrasse, Germany) 20220617 44

In this paper, we present an unprecedented and general umpolung protocol that allows the functionalization of silyl enol ethers and of 1,3-dicarbonyl compounds with a large range of heteroatom nucleophiles, including carboxylic acids, alcohols, primary and secondary amines, azide, thiols, and also anionic carbamates derived from CO<sub>2</sub> . The scope of the reaction also extends to carbon-based nucleophiles. The reaction relies on the use of 1-bromo-3,3-dimethyl-1,3-dihydro-1λ<sup>3</sup> [ ...[more]

PMID: 35638139

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