Renaissance in Alkyne Semihydrogenation: Mechanism, Selectivity, Functional Group Tolerance, and Applications in
Rafał Kusy1,2, Karol Grela2,3
1Leibniz-Institute for Catalysis, Albert-Einstein-Street 29a, 18059 Rostock, Germany.
This review highlights recent advances in alkyne semihydrogenation, a key method for producing alkenes. It focuses on overcoming challenges like over-reduction and improving catalyst selectivity for diverse applications.
Area of Science:
- Organic Chemistry
- Catalysis
- Chemical Synthesis
Background:
- Alkenes are vital industrial chemicals.
- Semihydrogenation of alkynes is a primary route to alkenes.
- Challenges include selectivity, over-reduction, and functional group compatibility.
Purpose of the Study:
- To review developments in alkyne semihydrogenation (2010-2024).
- To highlight solutions for selectivity and over-reduction.
- To showcase applications and catalyst strategies.
Main Methods:
- Literature review of alkyne semihydrogenation studies.
- Analysis of mechanistic aspects, including unconventional systems.
- Compilation of catalytic systems and their efficiencies.
Main Results:
- Significant progress in controlling diastereoselectivity and preventing over-reduction.
- Demonstrated functional-group compatibility in various synthetic applications.
- Development of advanced catalytic systems for enhanced selectivity.
Conclusions:
- Alkyne semihydrogenation is a versatile and evolving synthetic tool.
- Catalyst design is crucial for achieving high selectivity and efficiency.
- The reviewed methods offer practical solutions for alkene synthesis.
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