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N2 hydrogenation from activated end-on bis(indenyl) zirconium dinitrogen complexes
Doris Pun1, Christopher A Bradley, Emil Lobkovsky
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.
Researchers synthesized novel end-on dinitrogen zirconocene complexes via sodium amalgam reduction. These complexes undergo hydrogenation to form hydrido zirconocene hydrazido compounds, showcasing a new pathway for dinitrogen activation.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Coordination Chemistry
Background:
- Bis(indenyl)zirconium dihalide complexes are precursors in organometallic synthesis.
- Dinitrogen (N2) activation and functionalization are key challenges in chemistry.
- Understanding metal-ligand bonding is crucial for catalytic processes.
Purpose of the Study:
- To synthesize and characterize novel end-on dinitrogen zirconocene complexes.
- To investigate the structural and electronic properties of these complexes.
- To explore the reactivity of dinitrogen complexes toward hydrogenation.
Main Methods:
- Sodium amalgam reduction of bis(indenyl)zirconium dihalide complexes.
- X-ray crystallography for structural determination.
- Reaction of dinitrogen complexes with dihydrogen for hydrogenation studies.
Main Results:
- Synthesis of end-on dinitrogen zirconocene complexes with included salt.
- Structural analysis revealed short Zr-N and elongated N-N bonds, indicating N2 activation.
- Hydrogenation led to hydrido zirconocene hydrazido compounds and salt elimination.
Conclusions:
- A new structural type of zirconocene dinitrogen complex has been established.
- End-on coordination of dinitrogen is sufficient for hydrogenation.
- This work provides new insights into dinitrogen activation and functionalization pathways.
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