Copper-Catalyzedpara-Selective C–H Amination of Electron-Rich Arenes

Abstract

A one-pot two-step method for para-selective C–H amination of carbocyclic arenes comprises the in situ formation of unsymmetrical diaryl-λ3-iodanes followed by their Cu­(I)-catalyzed reaction with a range of N-unprotected amines.

Site-Selective Copper-Catalyzed Amination and Azidation of Arenes and Heteroarenes via Deprotonative Zincation

“…1–2 Recent developments in direct C–H amination provide an attractive strategy 3 that streamlines the synthesis of aminoarenes without the need of prefunctionalization of arene precursors (Scheme 1). 4–7 (5, 6, 7) To achieve selective C–H amination reactions, an innate approach that is independent of arene substrates would be an ideal strategy. While notable progress has been achieved by steric or electronic control (Scheme 1, I), unambiguous selectivity remains challenging in many cases where reactions give multiple isomers of aminated arenes.…”

“…While notable progress has been achieved by steric or electronic control (Scheme 1, I), unambiguous selectivity remains challenging in many cases where reactions give multiple isomers of aminated arenes. 4 Among arene substrate-guided strategies, selective amination of electron-deficient arenes has been commonly achieved via directed metalation of acidic aromatic C–H bonds. 5 Simple, non-activated arenes, however, are more challenging, though such aminoarenes constitute one of the most common amine skeletons of well-recognized importance (Figure 1).…”

Metal-Catalyzed and Metal-Free Intermolecular Amination of Light Alkanes and Benzenes

“…An elegant one-pot, two-step methodology has been developed by Suna and co-workers 77 to effect copper-mediated amination of benzenes by transiently generated unsymmetrical diaryl- λ 3 -iodanes. As opposed to the usually employed sulfonamides, amides and imides, simple amines are easily oxidized by monoaryl- λ 3 -iodanes, but are fairly stable towards the diaryl congeners.…”

Copper‐ and Cobalt‐Catalyzed Syntheses of Thiophene‐Based Tertiary Amines

“…Owing to a picolinamide directing group, morpholine can be introduced onto thiophene in the presence of a copper(II)‐catalyst and PhI(OAc) 2 as oxidant . The in situ formation of diaryl‐λ3‐iodanes followed by copper(I)‐catalyzed reaction with morpholine can be similarly applied to thiophene in average yields . Provided that a carboxamide group is present, ruthenium(II)‐catalyzed C‐H amination of thiophenes can be performed with N ‐(benzoyloxy)morpholine in moderate yields .…”

“…[11] The in situ formation of diaryl-λ3-iodanes followed by copper(I)-catalyzed reaction with morpholine can be similarly applied to thiophene in average yields. [12] Provided that a carboxamide group is present, ruthenium(II)-catalyzed C-H amination of thiophenes can be performed with N-(benzoyloxy)morpholine in moderate yields. [13] The use of O-benzoyl hydroxylamines (BzO-NR 2 ) to intercept thienylmetals under copper(I)-catalysis displays a broader substrate scope, and has been developed from arylmetals prepared by C-H lithiationtransalumination [14] and, above all, by deprotozincation.…”