Related Experiment Video
Updated: Jan 11, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
1,8-Di(2-ethynylaryl)biphenylenes: Palladium-Catalyzed Intramolecular Cycloisomerization and Subsequent Thermal
Hsiang-Han Chen1, Chih-Hsuan Liu1, Wei-Ting Ou1
1Department of Chemistry, National Cheng Kung University, 70101 Tainan, Taiwan.
Abstract:
A cascade reaction for 1,8-dibromobiphenylene A with arylboronic acid B toward an unusual product C was comprehensively investigated. The initially formed Suzuki product D underwent an unprecedented palladium-catalyzed cycloisomerization, yielding E with a unique 5-8-5-membered ring framework. In most cases, E proceeded via thermal rearrangement to form C. This work also examined the scope and limitations of the cascade reaction, probed its mechanism, and verified the structures of C and E by X-ray crystallography.
More Related Videos
11:44Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
09:12[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Related Concept Videos
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Thermal and Photochemical Electrocyclic Reactions: Overview
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.
Cycloaddition Reactions: Overview
Cycloaddition Reactions: MO Requirements for Thermal Activation