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A Simple Nickel Catalyst Enabling an E-Selective Alkyne Semihydrogenation.

ABSTRACT: Stereoselective alkyne semihydrogenations are attractive approaches to alkenes, which are key building blocks for synthesis. With regards to the most atom-economic reducing agent dihydrogen (H₂ ), only few catalysts for the challenging E-selective alkyne semihydrogenation have been disclosed, each with a unique substrate scope profile. Here, we show that a commercially available nickel catalyst facilitates the E-selective alkyne semihydrogenation of a wide variety of substituted internal alkynes. This results in a simple and broadly applicable overall protocol to stereoselectively access E-alkenes employing H₂ , which could serve as a general method for synthesis.

SUBMITTER: Thiel NO

PROVIDER: S-EPMC7027572 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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A Simple Nickel Catalyst Enabling an E-Selective Alkyne Semihydrogenation.

Thiel Niklas O NO Kaewmee Benyapa B Tran Ngoc Trung T Teichert Johannes F JF

Chemistry (Weinheim an der Bergstrasse, Germany) 20200121 7

Stereoselective alkyne semihydrogenations are attractive approaches to alkenes, which are key building blocks for synthesis. With regards to the most atom-economic reducing agent dihydrogen (H<sub>2</sub> ), only few catalysts for the challenging E-selective alkyne semihydrogenation have been disclosed, each with a unique substrate scope profile. Here, we show that a commercially available nickel catalyst facilitates the E-selective alkyne semihydrogenation of a wide variety of substituted inter ...[more]

PMID: 31691388

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