Copper-Catalyzed Three-Component Synthesis of 3-Aminopyrazoles and 4-Iminopyrimidines via β-Alkynyl-<i>N</i>-sulfonyl Ketenimine Intermediates
作者:Yanpeng Xing、Binyu Cheng、Jing Wang、Ping Lu、Yanguang Wang
DOI:10.1021/ol502302w
日期:2014.9.19
4-iminopyrimidines were efficiently prepared via copper-catalyzedthree-componentreactions of butadiynes, sulfonylazides, and hydrazides or imidamides. The reactions were regioselectively approached via the formation of a β-alkynyl-N-sulfonyl ketenimine intermediate which represented a new and effective 1,3-dielectrophilic equivalent in organic synthesis.
Controllable Site-Selective Construction of 4- and 5-Hydroxyalkyl-Substituted Imidazoles from Amidines, Ynals, and Water
作者:Wei Liu、Jiaming He、Xiang Liu、Yue Yu、Yongyan Pei、Baofu Zhu、Hua Cao
DOI:10.1021/acs.joc.0c01715
日期:2020.12.4
site-selective pathways to construct 4- and 5-hydroxyalkyl-substituted imidazoles through a three-component reaction of amidines, ynals, and water has been documented. Particularly, the high regioselectivity of the reaction was simply switched by changing the additives. In addition, further 18O-labeled experiments to probe a plausible mechanism and the gram-scale synthesis were studied.
Metal-Free Synthesis of Polysubstituted Imidazolinone Through Cyclization of Amidines with 2-Substituted Acrylates
作者:Zhen Liu、Yan-Shun Zhang、Yin Wei、Min Shi
DOI:10.1002/ejoc.201901687
日期:2020.3.8
A facile metal‐free cascade nucleophilic cyclization of amidines with 2‐substituted acrylates has been developed, producing polysubstituted imidazolinone derivatives in moderate to good yields with a broad substrate scope.
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