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Unsaturated platinum-rhenium cluster complexes. Synthesis, structures and reactivity.
Richard D Adams1, Burjor Captain, Mark D Smith
1Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA. adams@mail.chem.sc.edu
Journal of the American Chemical Society
|April 19, 2007
Summary
New platinum-rhenium (Pt-Re) metal clusters were synthesized and characterized. These clusters exhibit unique reactivity, including hydrogen addition and CO insertion, offering insights into metal cluster chemistry and catalysis.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Materials Science
Background:
- Metal clusters are crucial in catalysis and materials science.
- Understanding the synthesis and reactivity of heteronuclear metal clusters is essential for developing new functional materials.
Purpose of the Study:
- To synthesize and characterize novel platinum-rhenium (Pt-Re) metal cluster compounds.
- To investigate the reactivity of these clusters, particularly their response to hydrogen and carbon monoxide.
Main Methods:
- Reaction of platinum and rhenium precursors at varying temperatures.
- Characterization using spectroscopic techniques (e.g., NMR) and X-ray crystallography.
- Computational studies (Density Functional Theory) to elucidate structures and reaction mechanisms.
Main Results:
- Synthesis of new Pt-Re clusters with butterfly and triangular geometries.
- Observation of hydrogen addition to an unsaturated Pt2Re2 cluster, forming a tetrahydrido complex.
- Demonstration of CO insertion into a Pt-Pt bond and elimination of H2 from the tetrahydrido complex.
- Formation of known five-metal clusters upon reaction with additional platinum precursors.
Conclusions:
- Novel Pt-Re clusters with diverse structures and bonding motifs were successfully synthesized.
- The synthesized clusters display dynamic reactivity, including reversible H2 addition and CO insertion.
- Computational analysis supports proposed structures and reaction pathways, providing a deeper understanding of cluster behavior.
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