Bifunctional Salen-Cu(II) complex as efficient catalyst for N-arylation of imidazoles and Suzuki-Miyaura coupling reactions

Abstract

Bifunctional Salen-Cu(II) complex catalyzed cross-coupling reactions of aryl halids with imidazoles or phenylboronic acid reagents have been developed as practical methods for C-N and C-C bond formation. The procedure tolerates aryl halides with various functional groups(such as methoxy, acetyl, nitrile, fluoro and nitro groups) and gives the corresponding coupling products in moderate to high yields. The catalyst remained active after five successive catalytic runs without loss in performance.

Construction of porphyrin-based photocatalyst comprising pyridinium ionic liquid moiety for the metal-free visible light-assisted N-arylation of amines: facile approach to afford drug intermediates

“…20,21 Presently, the area of C-N functionalization, which involves triggering inert aryl chlorides, has attracted substantial attention as a novel technique for the transformation of simple precursors into industrially encouraging compounds. In 2014, the Wang group 22 sensitively revealed C-N bond formation using a homogeneous salen phosphonium copper(II) complex in the presence of sodium hydroxide and DMF at 100 1C. Employing a simple homogeneous catalytic method, a variety of imidazole derivatives was obtained, tolerating electronwithdrawing and donating groups and the salen complex could be reused in five successive cycles.…”

Combined experimental/theoretical study ofd-glucosamine promoted Ullmann-type C–N coupling catalyzed by copper(i): does amino really count?

“…4 The prospect of Ullmann coupling reaction catalyzed by copper catalysts is to perform such processes in more economic way. Up till now, while various ligands such as diamines, 3,5 glycol, 6 Schiff base, 4,7 amino acids, 8 diketones, 9 phenanthroline, 10 2,2 0 -bipyridine, 11 carbohydrates, 12 oxalamic acid, 13 diamide, 14 have already been proved efficient for promoting the targeted coupling reactions, it is always challenging and interesting to develop eco-friendly and more efficient ligand, 15 as well as to unravel the associated mechanistic aspects.…”