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Updated: Jun 8, 2026
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Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Late-transition-metal complexes as tunable Lewis bases
Jürgen Bauer1, Holger Braunschweig, Peter Brenner
1Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 14, 2010
Summary
Researchers synthesized novel platinum(0) complexes with N-heterocyclic carbenes (NHCs) and phosphanes. These complexes exhibit enhanced Lewis basicity, confirmed by aluminum chloride adduct formation and transfer reactions.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
Background:
- N-heterocyclic carbenes (NHCs) are versatile ligands in organometallic chemistry.
- Platinum complexes are important in catalysis and materials science.
- Tuning Lewis basicity of metal centers is crucial for reactivity control.
Purpose of the Study:
- To synthesize and characterize the first heteroleptic N-heterocyclic carbene (NHC)-phosphane platinum(0) complexes.
- To investigate the influence of NHC ligands on the Lewis basicity of platinum(0) complexes.
- To form and study Lewis acid-base adducts with aluminum chloride.
Main Methods:
- Synthesis of novel platinum(0) complexes featuring both NHC and phosphane ligands.
- Spectroscopic (NMR, IR) and structural (X-ray diffraction) characterization.
- Computational studies (DFT) to analyze electronic properties.
- Lewis acid-base adduct formation with aluminum chloride.
- Experimental validation using a transfer reaction.
Main Results:
- Successful synthesis of the first heteroleptic NHC-phosphane platinum(0) complexes.
- Spectroscopic, structural, and computational data indicate enhanced Lewis basicity of NHC-containing complexes.
- Formation of stable Lewis acid-base adducts with aluminum chloride.
- A transfer reaction provided conclusive experimental evidence for the increased Lewis basicity.
Conclusions:
- NHC ligands significantly enhance the Lewis basicity of platinum(0) complexes.
- These novel complexes offer tunable electronic properties for catalytic applications.
- The findings provide a deeper understanding of ligand effects on metal center reactivity.
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