Copper-Catalyzed Regioselective Remote C–H Bond Chalcogenation of Aromatic Amine Derivatives without Using Any Large Template

Abstract

A mild and convenient strategy has been developed for the para-selective chalcogenation of anilide scaffolds via C–H bond functionalization. This methodology employs one of the most earth-abundant and inexpensive Cu(II) catalysts and a commercially available simple aryl chalcogen source without any complex directing template, exogenous ligand, acid/base, oxidant, or other additives. The key feature of this methodology is an impressive regioselectivity along with a wide range of functional group tolerance with good to excellent yields under aerobic conditions.

Copper‐Promoted Oxidative Amide‐Assisted Radical Selenylation of Anilides and N‐Arylsulfonamides with Diselenides

“…On the basis of above experimental evidence and related literature, [11,[14][15][16] plausible reaction mechanisms of these selenylation processes are proposed in Scheme 4. Initially, copper (II) readily formed weak ligands with substrate A, [11] which promoted one-electron oxidation of the anilides A by Cu(II), resulting in the formation of N-phenyl acetamide radical B and Cu(I). [15,16] Afterwards, Cu(I) underwent oxidization by diphenyl diselenide to from PhSe * and regenerate Cu(II).…”

“…Recently, during the preparation of this article, Chatterjee et al have reported the para-selective selenylation of CÀ H bonds in benzoyl aromatic amines under copper-catalyzed aerobic reaction conditions (Scheme 1d, up). [11] Coincidentally, we have also achieved selectivity for para-selenylation in this work, although we initially studied ortho-site selenylation reactions.…”

Silver‐Catalyzed para‐Selective Sulfenyl Group Transfer Reactions of N‐Sulfenylanilides

“…Given that N ‐sulfenylanilides 1 a and 1 y , which were derived from crossover between the starting materials 1 c and 1 h , were not observed, the transfer of the sulfenyl group likely proceeds in an intermolecular manner. It should be noted that the reaction of anilide 3 a and disulfide 4 a under the standard conditions did not yield 2 a (Scheme 5c), eliminating the possibility that this transformation proceed through intermolecular reaction between anilide 3 and disulfide 4 [14k] …”