A Simple Nickel Catalyst Enabling an E-Selective Alkyne Semihydrogenation.
Niklas O Thiel1, Benyapa Kaewmee1, Trung Tran Ngoc1
1Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623, Berlin, Germany.
This study presents a nickel catalyst for efficient E-selective alkyne semihydrogenation using dihydrogen (H₂). The method provides a simple and broadly applicable protocol for synthesizing valuable E-alkenes.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Stereoselective synthesis of alkenes is crucial for organic chemistry.
- Dihydrogen (H₂) is an atom-economical reducing agent for alkyne semihydrogenation.
- Few catalysts exist for challenging E-selective alkyne semihydrogenation.
Purpose of the Study:
- To develop a broadly applicable protocol for E-selective alkyne semihydrogenation.
- To utilize a commercially available nickel catalyst for this transformation.
- To provide a simple method for synthesizing E-alkenes.
Main Methods:
- Employing a commercially available nickel catalyst.
- Utilizing dihydrogen (H₂) as the reducing agent.
- Investigating the semihydrogenation of various substituted internal alkynes.
Main Results:
- The nickel catalyst effectively facilitates E-selective alkyne semihydrogenation.
- A wide range of substituted internal alkynes were successfully converted to E-alkenes.
- The protocol demonstrates broad substrate scope and applicability.
Conclusions:
- A simple and broadly applicable protocol for E-selective alkyne semihydrogenation has been established.
- This method offers a valuable approach for stereoselective E-alkene synthesis.
- The developed protocol could serve as a general synthetic method.
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