Related Experiment Video
Updated: Jun 8, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Dicationic tellurium analogues of the classic N-heterocyclic carbene
Jason L Dutton1, Paul J Ragogna
1Department of Chemistry, The University of Western Ontario, 1151 Richmond St. London, Ontario, N6A 5B7 Canada.
Abstract:
The synthesis and comprehensive characterization of the first dicationic tellurium analogues of N-heterocyclic carbenes (NHCs) has been reported, in both the +2 and +4 oxidation states. For the +2 oxidation state, a base-stabilized form of TeCl(2) is used as the starting material. The dications are isolated by means of halide metathesis and the solid-state structures confirm the previously calculated diimine bonding arrangement. For Te(IV), a diamine is used in a high-yielding dehydrohalogen coupling reaction from TeCl(4). The dicationic NHC analogue is isolated in a base-stabilized form through halide abstraction and subsequent coordination by pyridine.
More Related Videos
19:58Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
09:45Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Related Concept Videos
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group with both...
Aromatic Hydrocarbon Anions: Structural Overview
Due to the absence of continuous overlap of p...
Predicting Molecular Geometry
Thermal Electrocyclic Reactions: Stereochemistry
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.
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions