Related Experiment Video
Updated: May 25, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Switching between ring closed and open N-incorporated heterocycles with tuneable charges and modular reactivity based
Roslyn Eadie1, Craig Richmond, Samantha Moreton
1WestCHEM, School of Chemistry, University of Glasgow, Glasgow, United Kingdom.
Abstract:
5-(2-bromoethyl)phenanthridinium bromide (BEP) undergoes a 3-step-one-pot cyclisation reaction with primary amines allowing the facile synthesis of a vast library of heterocycles. A diverse range of primary aryl amines were explored as reactants to gain insight into the product isolated as a result of the steric and electronic effects of the aryl precursors. Analysis and reaction monitoring with UV-vis and NMR spectroscopy revealed that excessively electron withdrawing groups and sterically hindered amines do not allow for isolation of the common neutral tetrahydroimidazophenanthridine (TIP) structure but allow either the isolation of the charged dihydroimadazophenanthridinium (DIP) or aminoethylphenanthridinium (AEP) products.
Related Concept Videos
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
Thermal and Photochemical Electrocyclic Reactions: Overview
Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
meta-Directing Deactivators: –NO2, –CN, –CHO, –⁠CO2R, –COR, –CO2H

