Copper-Catalyzed Intramolecular C−N Bond Formation: A Straightforward Synthesis of Benzimidazole Derivatives in Water
摘要:
A straightforward, efficient, and more sustainable copper-catalyzed method has been developed for intramolecular N-arylation providing the benzimidazole ring system. With Cu2O (5 mol %) as the catalyst, DMEDA (10 mol %) as the ligand, and K2CO3 as the base, this protocol was applied to synthesize a small library of benzimidazoles in high yields. Remarkably, the reaction was exclusively carried out in water, rendering the methodology highly valuable from both environmental and economical points of view.
Synthesis of 4-Aminoquinazolines by Palladium-Catalyzed Intramolecular Imidoylation of N-(2-Bromoaryl)amidines
作者:Gitte Van Baelen、Sander Kuijer、Lukáš Rýček、Sergey Sergeyev、Elwin Janssen、Frans J. J. de Kanter、Bert U. W. Maes、Eelco Ruijter、Romano V. A. Orru
DOI:10.1002/chem.201102468
日期:2011.12.23
investigated the intramolecular imidoylative cross‐coupling of N‐(2‐bromoaryl)amidines, leading to 4‐aminoquinazolines. After thorough optimization of the reaction with respect to palladium source and loading, ligand, base, temperature, and solvent, a small library of 4‐aminoquinazolines was prepared to determine the scope of this method. Various substituents are tolerated on the amidine and the isocyanide