Iron‐Catalysed Direct Aromatic Amination withN‐Chloroamines

Abstract

An optimized procedure for the direct intra‐ and intermolecular amination of aromatic C–H bonds with aminium radicals generated from N‐chloroamines under iron catalysis is reported. A range of substituted tetrahydroquinolines could be readily prepared, while extension to the synthesis of benzomorpholines was more limited in scope. A direct one‐pot variant was developed, allowing direct formal oxidative N–H/C–H coupling.

Directed Copper-Catalyzed Intermolecular Aminative Difunctionalization of Unactivated Alkenes

“…The harsh conditions required for the generation, intrinsic nucleophilic nature, and instability have greatly limited their broad applicability in both academic and industrial settings. In recent years, alkyl aminium radical cations (ARCs), the protonated or Lewis acid complexed counterparts of aminyl radicals, have emerged as powerful electrophiles in highly polarized radical processes such as intermolecular aryl C–N bond formation . However, the intermolecular functionalization of unactivated alkenes without polarization remains challenging.…”

The advent of electrophilic hydroxylamine-derived reagents for the direct preparation of unprotected amines

“…154 The same group reported the Fe catalysed intramolecular aromatic C-H amination of N-chloroamines with methanesulfonic acid to generate tertiary tetrahydroquinolines. 155 The group of Shibasaki exploited the labile N-O bond of hydroxylamine-derived compounds and developed the Rh catalysed synthesis of novel b-amino acids, which were generated from initial N-O bond cleavage in the substrate, followed by intramolecular C-H arene amination of the liberated amine moiety (Scheme 11E). 156 With this method a variety of tetrahydroquinoline derivatives and spirocyclic b-amino acids could be prepared.…”

A new outlook in oxidative transformations and coupling reactions via in situ generation of organic chloramines

“…In 2019, Stephen [ 85 ] and coworkers developed an iron‐catalyzed direct intra‐ and intermolecular amination of aromatic C–H bonds with aminium radicals via in situ generation of the N ‐chloramines (Scheme 41). A series of substituted tetrahydroquinolines could be easily prepared.…”