Copper Nanoparticles Supported on Zinc Oxide as Efficient Catalyst for the N‐Arylation of (Hetero)cyclic and Acyclic Amides

Abstract

Copper nanoparticles (CuNPs) supported on ZnO are highly active and selective heterogeneous catalyst for the N-arylation of cyclic and acyclic amides (Golberg coupling). The reaction conditions are mild, featuring K 3 PO 4 as a base and N,N'dimethylethylendiamine (DMEDA) as ligand in refluxing acetonitrile. The CuNPs/ZnO catalyst can be recovered and reused in six cycles with only little loss of activity. The methodology can be successfully scaled up to gram scale without decreasing the catalytic activity.

N,N′-Dimethylurea as an efficient ligand for the synthesis of pharma-relevant motifs through Chan–Lam cross-coupling strategy

“…83,84 Primary amides do not undergo N-arylation readily and there are few easily adoptable methods for arylation. They have been previously reported to be N-arylated with diazonium salts, 85 Goldberg arylating agentaryl halides, [86][87][88][89][90][91] aryltrimethoxysilane, 92 iodoferrocene, 93 and hetero(aryl) electrophiles. 94,95 However, very few studies have been executed with boronic acid and its derivatives.…”

Recent advances in the application of nanocatalysts in C‐N coupling reactions

“…Quite recently, copper NPs supported on zinc oxide were employed as a nanocatalyst for the N ‐arylation reaction by Moglie et al [ 211 ] The Cu NPs/ZnO was prepared by the addition of commercially available zinc oxide to a suspension of Cu NPs generated using anhydrous copper (II) chloride, lithium sand, and 4,4′‐di‐tert‐butylbiphenyl as the electron carrier. The system was tested in a series of Goldberg coupling reactions, including the coupling of (hetero) cyclic and acyclic amides with aryl halides (Scheme 77).…”