Related Experiment Video
Updated: Dec 20, 2025
09:45
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
10.8K
Iodination of cyclo-E5 -Complexes (E=P, As)
Helena Brake1, Eugenia Peresypkina1, Alexander V Virovets1
1Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany.
Angewandte Chemie (International Ed. in English)
|May 29, 2020
Summary
This study details the synthesis of novel metal-phosphorus and metal-arsenic complexes. New tripodal ligands and triple-decker complexes were formed through iodination reactions, expanding organometallic chemistry.
Area of Science:
- Organometallic Chemistry
- Inorganic Synthesis
- Coordination Chemistry
Background:
- Exploration of metal-phosphorus and metal-arsenic cluster chemistry.
- Synthesis of cyclopentadienyl metal complexes with P5 and As5 ligands.
Purpose of the Study:
- To investigate the reactivity of [Cp*M(η5-P5)] and [Cp*M(η5-As5)] complexes with iodine.
- To synthesize and characterize novel phosphorus and arsenic-containing metal complexes.
Main Methods:
- High-yield one-pot synthesis reactions.
- Iodination of pre-formed metal-phosphorus and metal-arsenic complexes.
- X-ray crystallography for structural determination.
Main Results:
- Selective formation of [Cp*MP6I6]+ salts with unprecedented all-cis tripodal triphosphino-cyclotriphosphine ligands.
- Synthesis of di-cationic Fe-As triple decker complex [(Cp*Fe)2(μ,η5:5-As5)][As6I8] and the first Ru-As5 triple decker complex [(Cp*Ru)2(μ,η5:5-As5)][As6I8]0.5.
- Isolation of rare [As6I8]2- and [As4I14]2- anions and novel dinuclear ruthenium-arsenic complexes with unique arsenic cluster structures.
Conclusions:
- Successful synthesis of novel metal-phosphorus and metal-arsenic complexes via iodination.
- Discovery of new ligand types and triple-decker complexes, expanding the scope of organometallic cluster chemistry.
- Demonstration of diverse reactivity patterns of M-P and M-As bonds under iodination conditions.
More Related Videos
Related Concept Videos
01:18Aromatic Hydrocarbon Cations: Structural Overview
3.5K
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...
Removing one hydrogen from the intervening CH2 group...
3.5K
01:16Cycloaddition Reactions: Overview
3.3K
Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
3.3K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
2.1K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
2.1K
![[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2Ffiles%2Fmedia%2Fscience-education%2Fscience-education-thumbs%2F12417.jpg&w=3840&q=75)
01:16[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
12.0K
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
12.0K
01:18Aromatic Hydrocarbon Anions: Structural Overview
3.4K
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...
Due to the absence of continuous...
3.4K
01:17Thermal Electrocyclic Reactions: Stereochemistry
2.4K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
2.4K