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Stereospecific Synthesis of E-Alkenes through Anti-Markovnikov Hydroalkylation of Terminal Alkynes.

ABSTRACT: We have developed a method for stereospecific synthesis of E-alkenes from terminal alkynes and alkyl iodides. The hydroalkylation reaction is enabled by a cooperative action of copper and nickel catalysts and proceeds with excellent anti-Markovnikov selectivity. We demonstrate the broad scope of the reaction, which can be accomplished in the presence of esters, nitriles, aryl bromides, ethers, alkyl chlorides, anilines, and a wide range of nitrogen-containing heteroaromatic compounds. Mechanistic studies provide evidence that the copper catalyst activates the alkyne by hydrocupration, which controls both the regio- and diastereoselectivity of the overall reaction. The nickel catalyst activates the alkyl iodide and promotes cross coupling with the alkenyl copper intermediate.

SUBMITTER: Hazra A

PROVIDER: S-EPMC7304255 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Stereospecific Synthesis of E-Alkenes through Anti-Markovnikov Hydroalkylation of Terminal Alkynes.

Hazra Avijit A Chen Jason J Lalic Gojko G

Journal of the American Chemical Society 20190802 32

We have developed a method for stereospecific synthesis of E-alkenes from terminal alkynes and alkyl iodides. The hydroalkylation reaction is enabled by a cooperative action of copper and nickel catalysts and proceeds with excellent anti-Markovnikov selectivity. We demonstrate the broad scope of the reaction, which can be accomplished in the presence of esters, nitriles, aryl bromides, ethers, alkyl chlorides, anilines, and a wide range of nitrogen-containing heteroaromatic compounds. Mec ...[more]

PMID: 31373807

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