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04:51
Synthesis of Triazole and Tetrazole-Functionalized Zr-Based Metal-Organic Frameworks Through Post-Synthetic Ligand Exchange
Published on: June 23, 2023
Carbophosphazene-supported ligand systems containing pyrazole/guanidine coordinating groups
Vadapalli Chandrasekhar1, Venkatasubbiah Krishnan, Ramachandran Azhakar
1Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur-208016, India. vc@iitk.ac.in
Inorganic Chemistry
|February 18, 2011
Summary
New carbophosphazene ligands were synthesized and reacted with metal salts, leading to diverse coordination complexes. These studies reveal metal-assisted hydrolysis and varied coordination modes, impacting inorganic heterocyclic ring structures.
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Inorganic Heterocyclic Chemistry
Background:
- Carbophosphazene compounds are versatile ligands in coordination chemistry.
- Understanding their reactivity with transition metals is crucial for developing new materials and catalysts.
- Previous studies have explored phosphazene coordination, but carbophosphazene systems offer unique structural possibilities.
Purpose of the Study:
- To synthesize novel carbophosphazene-based coordination ligands.
- To investigate the reactivity of these ligands with copper(II) and palladium(II) chloride salts.
- To characterize the resulting metal complexes and elucidate their coordination modes and structural features.
Main Methods:
- Synthesis and structural characterization of five carbophosphazene ligands.
- Reaction of ligands with CuCl2 and PdCl2, followed by isolation and characterization of metal complexes.
- X-ray crystallography was employed to determine the precise structures of metalated products.
Main Results:
- Five carbophosphazene ligands with planar C2N3P rings were synthesized.
- Reactions with metal chlorides resulted in diverse products, including complexes with geminal and non-geminal coordination, and metal-assisted P-N hydrolysis.
- A carbodiphosphazane dimer was formed with K2PtCl4, indicating ligand degradation under certain conditions. The exocyclic P-N bonds in one complex proved robust.
Conclusions:
- Carbophosphazene ligands exhibit varied coordination behavior with transition metals.
- Metal-assisted hydrolysis of P-N bonds is a significant reaction pathway.
- Metalation influences the bond parameters of the inorganic heterocyclic rings, offering insights into ligand-metal interactions.
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