Copper-Catalyzed Intermolecular Oxidative Cyclization of Haloalkynes: Synthesis of 2-Halo-substituted Imidazo[1,2-a]pyridines, Imidazo[1,2-a]pyrazines and Imidazo[1,2-a]pyrimidines was written by Gao, Yang;Yin, Meizhou;Wu, Wanqing;Huang, Huawen;Jiang, Huanfeng. And the article was included in Advanced Synthesis & Catalysis in 2013.HPLC of Formula: 1314978-36-3 This article mentions the following:
An efficient copper-catalyzed method for the synthesis of 2-haloimidazopyridines with aminopyridines and haloalkynes using mol. oxygen as oxidant in a one-pot manner has been developed. In this process, the reaction appears to be very general and suitable for the construction of a variety of 2-halo-substituted imidazopyridines, imidazopyrazines, and imidazopyrimidines. E.g., in presence of Cu(OTf)2 in MeCN under 1 atm. O2, oxidative cyclization of 2-aminopyridine and PhCCBr gave 80% imidazo[1,2-a]pyridine derivative (I). The intermol. oxidative diamination of haloalkynes was achieved for the first time. Importantly, the mild reaction conditions and the efficient conversion of the alkyl-substituted haloalkynes are great improvements over the existing methods. Moreover, the resultant 2-haloimidazo[1,2-a]pyridines could be efficiently converted to other functionalized imidazopyridine products via substitution, coupling reactions, and other transformations, which further indicates potential applications of this method in synthetic and pharmaceutical chem. In the experiment, the researchers used many compounds, for example, 5-Chloropyridazin-3-amine (cas: 1314978-36-3HPLC of Formula: 1314978-36-3).
5-Chloropyridazin-3-amine (cas: 1314978-36-3) belongs to pyridazine derivatives. Pyridazine and phthalazine have quite different spectroscopic properties compared with their isomers, pyrazine and quinoxaline. Pyridazine and derivatives coordinate readily with transition metals to form complexes and catalysts with synthetic utility.HPLC of Formula: 1314978-36-3
Referemce:
Pyridazine – Wikipedia,
Pyridazine | C4H4N2 – PubChem