Catalytic Alkyne Semihydrogenation with Polyhydride Ni/Ga Clusters
Maximilian Muhr1,2, Hao Liang3, Lars Allmendinger4
1Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry, Chair of Inorganic and Metal-Organic Chemistry, Lichtenbergstraße 4, 85748, Garching, Germany.
Angewandte Chemie (International Ed. in English)
|July 6, 2023
Summary
A novel nickel-gallium cluster (Ni3Ga7) reversibly binds dihydrogen, forming polyhydride species. These clusters demonstrate catalytic activity in semihydrogenation, linking molecular and solid-state catalysis.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Catalysis
Background:
- Bimetallic clusters offer unique reactivity due to cooperative effects.
- Understanding hydrogen interactions with metal clusters is crucial for catalysis.
Purpose of the Study:
- To synthesize and characterize a decanuclear Ni3Ga7 cluster.
- To investigate its reversible reaction with dihydrogen.
- To explore the catalytic activity of the resulting polyhydride clusters.
Main Methods:
- Synthesis of the Ni3Ga7 cluster.
- Low-temperature 2D NMR spectroscopy for hydride speciation.
- Density Functional Theory (DFT) calculations for structural elucidation.
- Catalytic testing in semihydrogenation reactions.
Main Results:
- The Ni3Ga7 cluster reversibly forms di-, tetra-, and hexahydride species.
- Structural analysis of di- and tetrahydride species was achieved.
- The cooperative effect of Ni and Ga is essential for hydrogen uptake.
- The polyhydride clusters exhibit good selectivity in 4-octyne semihydrogenation.
Conclusions:
- This study presents the first example of a molecular Ni-Ga cluster exhibiting polyhydride formation and catalytic activity.
- It establishes a conceptual link between molecular clusters and solid-state materials in catalysis.
Keywords:
(Poly-) HydridesDensity Functional CalculationsMetal ClusterROESYSemihydrogenation CatalysisMore Related Videos
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