Related Experiment Video
Updated: Jul 19, 2026
08:25
Measuring Nitrite and Nitrate, Metabolites in the Nitric Oxide Pathway, in Biological Materials using the Chemiluminescence Method
Published on: December 25, 2016
A terminal Ni(III)-imide with diverse reactivity pathways.
Elzbieta Kogut1, Heather L Wiencko, Libei Zhang
1Department of Chemistry, Georgetown University, Box 571227, Washington, DC 20057-1227, USA.
Journal of the American Chemical Society
|August 11, 2005
Summary
Nickel(I) beta-diketiminate complexes were synthesized and reacted to form nickel-imido complexes. These complexes exhibit unique bonding and reactivity, including imido group transfer and radical character.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Coordination Chemistry
Background:
- Nickel complexes with beta-diketiminate ligands are versatile building blocks in synthesis.
- 13-electron nickel fragments are reactive intermediates for forming new metal-ligand bonds.
Purpose of the Study:
- To synthesize and characterize novel beta-diketiminate Ni(I) lutidine adducts.
- To explore the reactivity of these adducts as synthons for "naked" nickel fragments.
- To investigate the formation and properties of nickel-imido complexes.
Main Methods:
- Synthesis of Ni(I) lutidine adducts.
- Reactions with N3Ad to form Ni-imido complexes.
- X-ray crystallography for structural determination.
- Electron Paramagnetic Resonance (EPR) spectroscopy for electronic structure analysis.
Main Results:
- Synthesis of Ni(I) lutidine adducts and their use as synthons.
- Formation of a singly bridged imide with short Ni-Ni and Ni-N(imido) distances.
- Isolation of a Ni(III) terminal imide with a contracted Ni-N(imido) bond and significant multiple bond character.
- EPR studies revealing a rhombic environment and hyperfine coupling to the imido nitrogen.
- Demonstration of imido group transfer reactions and radical character of the imido nitrogen.
Conclusions:
- Beta-diketiminate Ni(I) complexes are effective precursors to reactive nickel fragments.
- The resulting nickel-imido complexes display unique structural and electronic properties.
- These complexes exhibit diverse reactivity, including imido group transfer and radical-based transformations.
Related Concept Videos
02:51Metal-Ligand Bonds
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...
02:34Structural Isomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
01:261° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
01:371° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
01:26Redox Titration: Other Oxidizing and Reducing Agents
Besides iodine, other oxidizing or reducing agents can serve as titrants in redox titrations. Common oxidizing titrants include KMnO4, cerium(IV), and K2Cr2O7. The choice of oxidizing titrants depends on factors like stability, cost, analyte strength, and reaction rate between the analyte and titrant. KMnO4 is a strong oxidizing titrant that reduces from Mn(VII) to Mn(II) in a highly acidic solution, simultaneously oxidizing the analyte to a higher oxidation state. In this case, KMnO4 acts as a...