A highly efficient Cu-catalyst system for N-arylation of azoles in water

Green alternative solvents for the copper-catalysed arylation of phenols and amides

“…The use of 2,6-dimethylphenol, hindered at both sides, considerably reduces the reactivity, and coupling products with 4-iodoanisole and 2-iodotoluene were obtained in 37% and 22% yield respectively (18)(19). The coupling of 3,5-dimethylphenol with 2-iodotoluene furnished 20 in 45% yield, but the reaction with 4-iodoaniline or 2-iodoaniline afforded 79% and 71% yield respectively (21)(22). No competing arylation of the amino group was observed in these cases.…”

“…17,21 Water is frequently used as a co-solvent for these processes in mixtures with DMSO or DMF. When water alone is used, the addition of a phase-transfer catalyst (PTC), 22 a polymeric additive, 23 or a surfactant 24 is often required for effective catalysis. A further disadvantage is the use of hydroxides as bases in these conditions, rather than carbonates or phosphates; these bases are known to be able to react with the aryl halide as nucleophiles, thus leading to the corresponding phenolic side products.…”

An efficient d-glucosamine-based copper catalyst for C–X couplings and its application in the synthesis of nilotinib intermediate

“…[7][8] They make the applicability of the reaction higher and avoid the phenomenon of the shift of double bonds which was caused by the eliminating of β-H when catalytic coupling by the Pd catalyst. At present, the C-N coupling catalyzed by copper has achieved fruitful results, 9-14 but some reactions often suffer from several drawbacks such as the use of stoichiometric copper catalysts, the high polarity and toxicity solvents, harsh reaction conditions, and special ligands including phenanthrolines, 15 amino acids, 16 diketones, 17 diamines, 18 oximes, 19 carbohydrates 20 and others, 21 some conditions above not only cause great waste, but also pollute the environment we live by.…”

Room Temperature N-Arylation of 1,2,4-Triazoles under Ligand-Free Condition

“…Recently, there was a report of Cu catalyzed N-arylation of azoles with aryl halide in presence of ligand but the longer reaction time and difficulty in separation of ligand limits the method [36], whereas in our method, we can easily separate CuO nanocatalyst and recycled it for at least five times without much loss in yield of the product.…”