914614-53-2Relevant academic research and scientific papers
Rhodium(III)-Catalyzed Selective Direct Olefination of Imidazoles
Zhao, Haoqiang,Xu, Jianbin,Chen, Changjun,Xu, Xin,Pan, Yixiao,Zhang, Zongyao,Li, Huanrong,Xu, Lijin
, p. 985 - 994 (2018)
Rhodium(III)-catalyzed chelation-assisted highly regio- and stereoselective direct olefination of imidazoles with olefins has been developed. A broad range of C2-substituted N-(2-pyrimidyl)imidazoles underwent smooth C5-olefination with both activated and unactivated olefins to furnish the corresponding products in good to excellent yields with high tolerance of functional groups on both coupling partners in the presence of a cationic rhodium(III) catalyst. The combination of a catalytic amount of Cu(OAc)2 (copper(II) acetate) and O2 (oxygen) serves as the terminal oxidant. This protocol strongly relies on the use of 2-substituted imidazoles as the substrates, and the presence of readily installable and removable pyrimidyl directing group was found to be critical for catalysis. Mechanistic studies suggest the involvement of a five-membered rhodacycle as the key intermediate in the catalytic cycle. The method can also be extended to the coupling reaction of benzimidazoles with olefins. (Figure presented.).
Cu(II)-catalyzed C-N coupling of (hetero)aryl halides and N-Nucleophiles promoted by α-benzoin oxime
Yuan, Chunling,Zhang, Lei,Zhao, Yingdai
, (2019/11/28)
We first reported the new application of a translate metal chelating ligand α-benzoin oxime for improving Cu-catalyzed C-N coupling reactions. The system could catalyse coupling reactions of (hetero)aryl halides with a wide of nucleophiles (e.g., azoles, piperidine, pyrrolidine and amino acids) in moderate to excellent yields. The protocol allows rapid access to the most common scaαolds found in FDA-approved pharmaceuticals.
Methyl-α-d-glucopyranoside as Green Ligand for Selective Copper-Catalyzed N-Arylation
Chen, Fengyang,Chen, Guoliang,Chen, Yuanguang,Du, Fangyu,Zhou, Qifan
, p. 4590 - 4600 (2019/12/11)
In the selective N-arylation of amines or azoles with aryl halidesa-, methyl-α-d-glucopyranoside (MG) was found to function as a green ligand of copper powder. In addition, nitrogen heterocyclic amine compounds can also undergo the N-arylation coupling with heterocyclic aryl chlorides. This process allows access to a variety of aromatic amines and aryl azoles under mild reaction conditions, has good tolerance, and proceeds in moderate to high yield.
N-arylations of nitrogen-containing heterocycles with aryl and heteroaryl halides using a copper(I) oxide nanoparticle/1,10-phenanthroline catalytic system
Tang, Bo-Xiao,Guo, Sheng-Mei,Zhang, Man-Bo,Li, Jin-Heng
, p. 1707 - 1716 (2008/12/22)
A general procedure for solvent-free N-arylations of nitrogen-containing heterocycles, i.e. imidazoles, triazoles, and indoles, with aryl and heteroaryl halides catalyzed by copper(I) oxide (Cu2O) nanoparticles is demonstrated. Four types of Cu2O were evaluated: the bulky compound and its cubic, octahedral, and spherical nanoparticulate forms. The results show that Cu2O nanoparticles, in particular the cubic form, are highly efficient for the N-arylation reaction. In the presence of cubic Cu2O nanoparticles, 1,10-phenanthroline, and tetrabutylammonium fluoride, a variety of nitrogen-containing heterocycles smoothly underwent N-arylation with aryl and heteroaryl halides at 110-145 °C to give the corresponding products in moderate to excellent yields. It is noteworthy that the reaction is conducted under solvent-free conditions. The reaction mechanism is also discussed.
2-Aminopyrimidine-4,6-diol as an efficient ligand for solvent-free copper-catalyzed N-arylations of imidazoles with aryl and heteroaryl halides
Xie, Ye-Xiang,Pi, Shao-Feng,Wang, Jian,Yin, Du-Lin,Li, Jin-Heng
, p. 8324 - 8327 (2007/10/03)
Efficient and solvent-free copper-catalyzed N-arylations of imidazoles with aryl and heteroaryl halides have been demonstrated. In the presence of CuBr, 2-aminopyrimidine-4,6-diol, and TBAF (n-Bu4NF), a variety of imidazoles underwent the N-arylation reaction with aryl and heteroaryl halides smoothly in moderate to excellent yields. Noteworthy is that the reaction is conducted under solvent-free conditions.
