Related Experiment Video
Updated: Dec 11, 2025
09:45
A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
31.8K
A versatile nitrogen ligand for alkaline-earth chemistry.
Peter M Chapple1, Marie Cordier, Vincent Dorcet
1Univ Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) - UMR 6226, F-35000 Rennes, France. yann.sarazin@univ-rennes1.fr.
Dalton Transactions (Cambridge, England : 2003)
|August 19, 2020
Summary
The {CarbDiPP} ligand stabilizes alkaline earth metal complexes, preventing decomposition common in these elements. This versatile ligand offers kinetic stabilization through steric bulk, though challenges remain in synthesizing specific hydride complexes.
Area of Science:
- Organometallic Chemistry
- Main Group Chemistry
Background:
- Alkaline earth metal (Ae) complexes often suffer from ligand redistribution and decomposition.
- Developing robust ligands is crucial for stabilizing reactive Ae centers.
Purpose of the Study:
- To synthesize and characterize novel alkaline earth metal complexes using the {CarbDiPP} ligand.
- To investigate the stabilizing effect of the {CarbDiPP} ligand on various Ae metals (Mg, Ca, Sr, Ba).
Main Methods:
- Synthesis of {CarbDiPP} ligand and its complexes with Mg, Ca, Sr, and Ba.
- Characterization using X-ray crystallography, NMR spectroscopy, and other spectroscopic techniques.
- Investigation of complex stability in solution and reactivity with PhSiH3.
Main Results:
- Structurally characterized complexes of Mg, Ca, Sr, and Ba with the {CarbDiPP} ligand were prepared.
- These complexes exhibit high stability in solution, resisting ligand redistribution.
- The {CarbDiPP} ligand provides kinetic stabilization via steric encapsulation of the metal centers.
- Attempts to synthesize heteroleptic Ae-hydrides resulted in reduction and hydrosilylation of the imine groups.
Conclusions:
- The {CarbDiPP} ligand is a versatile and effective tool for stabilizing alkaline earth metal complexes.
- Its steric properties are key to preventing decomposition pathways.
- While successful for various coligands, challenges exist in synthesizing specific hydride derivatives due to imine reactivity.
Related Concept Videos
01:22EDTA: Chemistry and Properties
3.0K
Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...
3.0K
02:51Metal-Ligand Bonds
23.3K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
23.3K
00:43Complexometric Titration: Ligands
2.1K
Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...
2.1K
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
695
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
695
01:19Complexation Equilibria: The Chelate Effect
978
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
978
03:06Alkali Metals
23.5K
Group 1 elements are soft and shiny metallic solids. They are malleable, ductile, and good conductors of heat and electricity. The melting points of the alkali metals are unusually low for metals and decrease going down the group, while the density increases going down the group with the exception of potassium (Table 1).
Table 1: Properties of the alkali metals
Table 1: Properties of the alkali metals
23.5K