Photoinduced Copper-Catalyzed Radical Aminocarbonylation of Cycloketone Oxime Esters

Abstract

A visible light-induced and exogenous photosensitizer-free, copper-catalyzed radical aminocarbonylation of cycloketone oxime esters with CO gas and amines is developed. The mild catalytic system involving CuCl and N,N,N-tridentate ligand shows good reactivity and chemoselectivity, and tolerates a wide range of cycloketone oxime esters and alkyl/aryl amines, giving the corresponding cyanoalkylated amides in moderate to good yields. Preliminary mechanistic studies suggest that the reaction involves a CuI/CuII/CuIII-based catalytic cycle and radical intermediate.

Selective C-C Bond Scission of Ketones via Visible-Light-Mediated Cerium Catalysis

“…[28][29][30] Several elegant photocatalytic C-C bond cleavage transformations of amine and alcohol feedstocks that utilize radical-mediated C-C bond scission strategy have been reported recently. [31][32][33][34][35][36][37][38][39][40][41] Although presenting intriguing opportunities, the utilization of visible-light energy for the direct cleavage of C-C bond of ketones remains largely elusive.…”

Recent Advances in Visible-Light-Promoted Copper Catalysis in Organic Reactions

“…The electron transfer is from the excited copper(I) complex to the NHP ester to form a copper(II) complex and produce the phthalimide anion (which binds to copper), CO2, and alkyl radical (which reacts with copper(II)phthalimide complex to give the coupling product and regenerate a copper(I) complex In 2019, A visible light-induced copper-catalyzed carbonnitrogen cross-coupling of cycloketone oxime esters, CO gas and amines has been developed by Chen group (Scheme 5). 17 The catalytic method, features in-situ formed photoexcited complex by CuCl, amine and N,N,N-tridentate ligand to promote the radical formation and further reaction with CO and amines. The reaction has a good reactivity, chemoselectivity and functional group tolerance.…”

“…In 2019, a visible-light-induced copper-catalyzed carbon-nitrogen cross-coupling of cycloketone oxime esters, CO gas, and amines was developed by the Chen group (Scheme 5). 17 The catalytic method features a photoexcited complex formed in situ from CuCl, amine and N,N,N-tridentate ligand to promote the radical formation and further reaction with CO and amines. The system has good reactivity, chemoselectivity and functional group tolerance.…”

Recent Developments in Radical Cross‐Coupling of Redox‐Active Cycloketone Oximes

“…In 2019, Xiao and co‐workers achieved a photoinduced copper‐catalyzed aminocarbonylation of cycloketone oxime esters 149 with CO and alkyl/aryl amines 150 (Scheme 51). [64] Electron‐rich and electron‐deficient substituted anilines 150 were well tolerated, affording the aminocarbonylation products 151 in 47–81% yields. In addition, α‐amino acid esters and sterically demanding primary amines also proceeded smoothly to give the corresponding amides in good yields.…”