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Updated: Jul 5, 2026
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A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions
Published on: February 5, 2016
Electronic structure of dinuclear gold(i) complexes.
1University of Maine Department.of Chemistry Orono Maine 04469-5706 USA.
Metal-Based Drugs
|May 14, 2008
Summary
Dinuclear gold(I) complexes with shorter phosphine ligands exhibit intramolecular interactions, enhancing reactivity with disulfides. Aurophilicity and Au(I)-Au(I) interactions influence reactivity and photochemical activity.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Photochemistry
Background:
- Dinuclear gold(I) complexes are of interest due to their unique electronic properties and potential applications.
- Understanding metal-metal interactions is crucial for predicting and controlling reactivity.
- Aurophilicity, the attractive interaction between gold(I) centers, plays a significant role in the behavior of these complexes.
Purpose of the Study:
- To investigate the influence of ligand structure on metal-metal interactions in dinuclear gold(I) complexes.
- To correlate these interactions with reactivity towards organic disulfides.
- To explore the relationship between aurophilicity, ligand type, and photochemical activity.
Main Methods:
- Cyclic voltammetry (CV) was employed to study electronic properties.
- Crystal structure analysis determined the nature and distance of Au(I)-Au(I) interactions.
- Quantum yield measurements quantified photochemical activity.
Main Results:
- A shorter bidentate phosphine ligand (dppm) in LL(AuSR*)(2) complexes led to broader anodic sweeps in CV, suggesting weak intramolecular Au(I)-Au(I) interactions.
- These interactions correlated with accelerated reaction rates with organic disulfides.
- Quantum yields for cis-dppee(AuX)(2) complexes were higher with softer halide ligands (X) and correlated with aurophilicity.
- Crystal structures revealed short intramolecular Au(I)-Au(I) distances in cis-dppee(AuI)(2) (2.95 Å) versus longer intermolecular distances in trans-dppee(AuI)(2) (3.23 Å).
- Substitution of phosphorus with arsenic (cis-dpaee) resulted in photochemically active complexes, albeit with lower quantum yields than their dppee counterparts.
Conclusions:
- Intramolecular Au(I)-Au(I) interactions, influenced by ligand bite angle and electronic effects, are critical for the reactivity of dinuclear gold(I) complexes.
- Aurophilicity is a key factor governing both reactivity and photochemical properties.
- Ligand design, including the choice of heteroatom (P vs. As), significantly impacts the photochemical behavior of these gold complexes.
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