Related Experiment Video
Updated: Oct 3, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Ring-opening fluorination of bicyclic azaarenes
Masaaki Komatsuda1, Ayane Suto1, Hiroki Kondo1
1Department of Applied Chemistry, Waseda University 513, Wasedatsurumakicho, Shinjuku Tokyo 169-8555 Japan junyamaguchi@waseda.jp.
Abstract:
We have discovered a ring-opening fluorination of bicyclic azaarenes. Upon treatment of bicyclic azaarenes such as pyrazolo[1,5-a]pyridines with electrophilic fluorinating agents, fluorination of the aromatic ring is followed by a ring-opening reaction. Although this overall transformation can be classified as an electrophilic fluorination of an aromatic ring, it is a novel type of fluorination that results in construction of tertiary carbon-fluorine bonds. The present protocol can be applied to a range of bicyclic azaarenes, tolerating azines and a variety of functional groups. Additionally, mechanistic studies and enantioselective fluorination have been examined.
Related Concept Videos
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Nomenclature of Aryl and Heterocyclic Amines
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview

