An Efficient Diamine·Copper Complex-Catalyzed Coupling of Arylboronic Acids with Imidazoles

Abstract

[formula: see text] A novel diamine.copper complex-catalyzed intermolecular coupling of arylboronic acids (1) with imidazoles (3) is described. In the presence of a catalytic amount of [Cu(OH).TMEDA]2Cl2 (2), arylboronic acids (1) react smoothly with imidazoles (3) in dichloromethane at room temperature to give a variety of N-arylimidazoles (4) in good to excellent yields.

Modern Synthetic Methods for Copper‐Mediated C(aryl)O, C(aryl)N, and C(aryl)S Bond Formation

“…[47] Scheme 20. Key step: Boronic acid (3 equiv), Cu(OAc) 2 (5 equiv), pyr/NMP, 80 8C, > 2 days; then optimized to: boronic acid (3 equiv), Cu(OAc) 2 (5 equiv), pyr/NMP, 4 molecular sieves, microwave heating (3 10 s 1000 W, 5 applications of reagents).…”

“…Aryl donors can be as follows: A3: Building on this proposal, Collman and Zhong [47] have proposed the follow catalytic cycle for the coupling of imidazole with aryl boronic acids (Scheme 109). Although, as yet, no experimental evidence exists for any of the putative steps, the hypothesis can be supported.…”

Recent applications of the Suzuki–Miyaura cross-coupling reaction in organic synthesis

“…In order to overcome these problems, Collman et al have recently reported the N-arylation of imidazoles with boronic acids in the presence of a catalytic amount of [Cu(OH)·TMEDA] 2 Cl 2 as the copper source (Scheme 157). 327 This procedure is not applicable, however, to the arylation of simple amines, anilines and phenols.…”

Five‐Membered Heterocycles: 1,3‐Azoles

“…Arylboronic acids 167 react efficiently with imidazoles 165 in the presence of a novel diamine-copper complex to give various N-arylimidazoles 168 (Scheme 10.83) [271].…”