99261-88-8Relevant academic research and scientific papers
Copper-Catalyzed Inter- and Intramolecular C-N Bond Formation: Synthesis of Benzimidazole-Fused Heterocycles
Rasheed, Sk.,Rao, D. Nageswar,Das, Parthasarathi
, p. 9321 - 9327 (2015/09/28)
A Cu (II)-catalyzed, inter/intramolecular C-N bond formation for the synthesis of various benzimidazole-fused heterocycles in a concise manner has been reported. The robustness of this reaction is demonstrated by the synthesis of a series of benzimidazole-fused heteroaromatics (e.g., pyrido[1,2-a] benzimidazole, benzimidazo[1,2-a]quinolines, benzimidazo [1,2-a]pyrazine, benzo[4,5] imidazo[2,1-b]thiazoles) directly from 2-aminoheteroarenens and 2-iodoarylboronic acids in one-pot. The novel cascade protocol for C-N bond formation operates via unique combination of Chan-Lam type coupling followed by Ullmann-type reaction.
Hypervalent iodine(iii) catalyzed oxidative C-N bond formation in water: Synthesis of benzimidazole-fused heterocycles
Rao, D. Nageswar,Rasheed,Vishwakarma, Ram A.,Das, Parthasarathi
, p. 25600 - 25604 (2014/07/07)
An iodine(iii) catalyzed C(sp2)-H functionalization- intramolecular amination reaction of N-aryl-2-amino-N-heterocycles has been developed in water and under ambient conditions. This metal-free open-flask chemistry is general and successfully applied in synthesizing the benzimidazole-fused heterocycles pyrido[1,2-a]benzimidazole, benzimidazo[1,2-a]quinoline and benzimidazo[2,1-a]isoquinoline derivatives. the Partner Organisations 2014.
A metal-free tandem demethylenation/C(sp2)-H cycloamination process of N -Benzyl-2-aminopyridines via C-C and C-N bond cleavage
Liang, Dongdong,He, Yimiao,Liu, Lanying,Zhu, Qiang
supporting information, p. 3476 - 3479 (2013/07/26)
A mild, metal-free synthesis of pyrido[1,2-a]benzimidazoles starting with N-benzyl-2-aminopyridines, which employs PhI(OPiv)2 as a stoichiometric oxidant, has been developed. The process is initiated by an unusual PhI(OPiv)2-mediated ipso SEAr reaction, followed by solvent-assisted C-C and C-N bond cleavage.
On the importance of an acid additive in the synthesis of pyrido[1,2-a]benzimidazoles by direct copper-catalyzed amination
Masters, Kye-Simeon,Rauws, Tom R. M.,Yadav, Ashok K.,Herrebout, Wouter A.,Van Der Veken, Benjamin,Maes, Bert U. W.
supporting information; experimental part, p. 6315 - 6320 (2011/07/31)
Not just an acid! An expedient and highly modular synthesis of 6-, 7-, and 8-substituted pyrido[1,2-a]benzimidazoles (4) has been developed by a direct intramolecular C-H amination of N-phenylpyridin-2-amines (3). Efficient C-H amination of 3 could only be achieved in the presence of catalytic copper and an acid additive. The type of acid (pKa) proved to be crucial for the catalysis. C-Cl aminations in N-(2-chloroaryl)pyridin-2-amines allow access to 9-substituted pyrido[1,2-a]benzimidazoles. Copyright
A direct intramolecular C-H amination reaction cocatalyzed by copper(II) and iron(III) as part of an efficient route for the synthesis of pyrido[1,2-a ]benzimidazoles from N-aryl-2-aminopyridines
Wang, Honggen,Wang, Yong,Peng, Changlan,Zhang, Jiancun,Zhu, Qiang
supporting information; experimental part, p. 13217 - 13219 (2010/11/04)
A novel and efficient synthesis of pyrido[1,2-a]benzimidazoles through direct intramolecular aromatic C-H amination of N-aryl-2-aminopyridines has been developed. The reaction, cocatalyzed by Cu(OAc)2 and Fe(NO 3)3?9H
