Ligand-free copper(i) oxide nanoparticle-catalysed amination of aryl halides in ionic liquids

Abstract

In the following, we present a simple and feasible methodology for a C-N coupling reaction using nanoscale Cu 2 O catalysts incorporated in n-Bu 4 POAc ionic liquid media. It is shown that a wide range of amines and aryl halides can be coupled selectively in high yields, without the use of ligands or additives (bases) and without precautions against water or air. All catalyses can be carried out with a nanoparticle catalyst loading as low as 5 mol%, based on the used precursor.

Tetragonal Cu2Se nanoflakes: synthesis using selenated propylamine as Se source and activation of Suzuki and Sonogashira cross coupling reactions

“…On the other hand copper(II) oxide nanoparticles have been used under ligand free conditions. 30 It is therefore worthwhile to see present catalytic activation with respect to literature reports on other copper containing nano-phases which have catalyzed such coupling reactions. Their number is of course small.…”

Nanostructured Cu2O Synthesized via Bipolar Electrochemistry

“…Another important application of Cu 2 O is to catalyze organic coupling reactions, including carbon-carbon [12], and nitrogen-carbon couplings [13]. Cu 2 O-catalyzed synthesis (with and without illumination) of amides via amidation of aryl halides [14], Sonogashira- [15], and Suzuki-type couplings [16,17], have shown excellent conversion with satisfactory yields under mild reaction conditions at much lower cost (as compared to palladium-catalyzed syntheses).…”

“…Cu 2 O-catalyzed synthesis (with and without illumination) of amides via amidation of aryl halides [14], Sonogashira- [15], and Suzuki-type couplings [16,17], have shown excellent conversion with satisfactory yields under mild reaction conditions at much lower cost (as compared to palladium-catalyzed syntheses). Moreover, a recyclable Cu 2 O nano-catalyst has been utilized for nitrogen-carbon cross coupling of aryl halides with aromatic/aliphatic amides [18] and amines [13], as well as numerous types of Cu 2 O-driven cycloaddition reactions (e.g., click chemistry [19], Huisgen cycloaddition [20]). The good selectivity and low toxicity, together with excellent yields of the Cu 2 O-catalyzed methods, make this an inexpensive catalyst that is especially important for up-scaled production.…”

Comparative Synthesis of Cu and Cu2O Nanoparticles from Different Copper Precursors in an Ionic Liquid or Propylene Carbonate

“…[7] Synthesis conditions such as temperature, solvent, reducing agent, and stabilizing agent can influence the size, size distribution, and shape of M-NPs. [8] Copper and copper oxide nano-to micromaterials are studied for catalytic CO oxidation, [9][10][11][12][13][14] alkyne-azide cycloadditions, [15][16][17] aryl-sulfur bond formation, [18,19] and amination of aryl halides, [20][21][22][23] among others. [24][25][26] Copper(I) oxide, Cu 2 O, is a metal oxide semiconductor with promising applications in solar energy conversion.…”