Related Experiment Video
Updated: Jan 15, 2026
10:52
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
3.3K
Water-Soluble Rhenium Nitride Complexes Supported by Multidentate Phosphinite Ligands Provide Insights into Aqueous
Noah D McMillion1, Mehrnaz Aliahmadi1, Quinton J Bruch1
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States.
Inorganic Chemistry
|October 14, 2025
Summary
Researchers explored rhenium nitride complexes in water for ammonia synthesis. A stable, water-soluble complex produced ammonium in water, showing potential for sustainable nitrogen fixation.
Area of Science:
- Inorganic Chemistry
- Catalysis
- Sustainable Chemistry
Background:
- Metal nitride complexes are crucial for ammonia synthesis.
- Utilizing water as a proton source in these reactions is desirable but underexplored.
- Rhenium nitride complexes offer potential for aqueous ammonia synthesis.
Purpose of the Study:
- To investigate the aqueous reactivity of rhenium nitride complexes.
- To develop water-stable nitride complexes for ammonia synthesis.
- To understand the factors influencing ammonium production in aqueous media.
Main Methods:
- Synthesis and characterization of rhenium nitride complexes with phosphinite ligands.
- Evaluation of ligand stability across a wide pH range (2-13).
- Structural analysis using hanging-drop crystallization and NMR spectroscopy.
- Ammonium yield determination via SmI2-mediated reduction in buffered aqueous solutions.
Main Results:
- A tetradentate ligand (6POphenOP) supported a water-soluble, pH-stable rhenium nitride complex.
- Structural and spectroscopic studies revealed coordination sphere changes in aqueous buffer and water-nitride hydrogen bonding.
- Ammonium was successfully synthesized from the rhenium nitride complex in buffered water.
- Ammonium yields were influenced by buffer concentration, suggesting buffer-metal coordination.
Conclusions:
- Stable, water-soluble rhenium nitride complexes can be synthesized and function in aqueous environments.
- Understanding buffer effects is key to optimizing aqueous ammonia synthesis.
- This work provides insights into aqueous nitrogen fixation using well-defined metal nitride complexes.
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