Related Experiment Video
Updated: Jul 19, 2026
05:33
Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications
Published on: August 12, 2013
A Five-Membered Ring with Three Negative Charges and Solvent-Free Lithium Counterions.
Scheschkewitz1, Menzel, Hofmann
1Fachbereich Chemie der Universität, D-35032 Marburg (Germany).
Angewandte Chemie (International Ed. in English)
|December 14, 1999
Summary
The study introduces the first compound featuring a negatively charged five-membered ring, stabilized by eta(5)-bound lithium ions. These lithium ions exhibit exceptionally short distances to the ring plane, offering new insights into organometallic chemistry.
Area of Science:
- Organometallic Chemistry
- Inorganic Chemistry
- Materials Science
Background:
- The synthesis and characterization of novel compounds with unique bonding and structural properties are crucial for advancing chemical understanding.
- Exploring compounds with charged ring systems can lead to new materials with tailored electronic and physical characteristics.
Purpose of the Study:
- To synthesize and characterize the first compound containing a triply negatively charged five-membered ring.
- To investigate the coordination behavior and structural features of eta(5)-bound lithium ions within this novel charged ring system.
Main Methods:
- Chemical reduction of a precursor compound (2) using lithium metal.
- X-ray crystallography for detailed structural analysis of the resulting lithium compound (1).
Main Results:
- Successful synthesis of compound 1, featuring a triply negatively charged five-membered ring.
- Observation of eta(5)-bound lithium ions coordinated to the ring.
- Determination of remarkably short distances between the lithium ions and the ring plane, indicating strong interactions.
Conclusions:
- The study presents a groundbreaking example of a stable, triply negatively charged five-membered ring system.
- The eta(5)-bound lithium ions demonstrate unique coordination, highlighting the influence of charge and ring structure on metal-ligand interactions.
Related Concept Videos
03:10Ionic Radii
Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it is smaller than the atom from which it is derived. For example, the covalent radius of an aluminum atom (1s22s22p63s23p1) is 118 pm, whereas the ionic radius of an Al3+ (1s22s22p6) is 68 pm. As electrons are removed from the outer valence shell, the remaining core electrons occupying smaller shells experience a greater effective nuclear...
02:48Ionic Bonding and Electron Transfer
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
03:45Formation of Complex Ions
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
01:18Aromatic Hydrocarbon Anions: Structural Overview
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous overlap of p...
Due to the absence of continuous overlap of p...
01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...