Iron, Indium Catalyze Amine-involved Coupling And Tandem Reactions

Propargylamines and quinoline derivatives are versatile synthetic intermediates for organic synthesis and important structural elements of natural products and therapeutic drug molecules. The synthesis of these compounds is very necessary. It is an effective strategy to build nitrogen-containing compounds using a metal-catalyzed organic reactions. Iron salts and Indium salts are often used as catalysts for organic reactions because of their less expensive, readily available and environmentally benign properties. Here, we reports iron-catalyzed ligand-free three-component tandem reactions of aldehydes, alkynes, and amines; iron (III)-catalyzed synthesis of substituted quinolines from styrene oxide with aromatic amines and indium-catalyzed highly efficient three-component coupling of aldehyde, alkyne, and amine via C-H bond activation.(1) In this paper, the synthesis of propargylamines by iron-catalyzed ligand-Free three-component tandem reactions of aldehydes, alkynes, and amines were reported in the first time. The reactions were carried out in the presence of catalytic amounts of FeCl₃ and in conjunction with 4 A molecular sieves without any ligand, and generated the corresponding propargylamines in good to excellent yields. The reactions were also applicable to aromatic and aliphatic aldehydes, alkynes, and aliphatic secondary amines.(2) In this paper, iron-catalyzed tandem reactions of aldehydes, terminal alkynes, and primary amines as a strategy for the synthesis of quinoline derivatives was reported. by condensation, addition, cyclization, oxidation reactions, the reaction provides the raw materials from the simple quinoline derivatives prepared an effective method, and proposed a possible reaction mechanism.(3) In this paper, a novel iron (III)-catalyzed synthesis of substituted quinolines from styrene oxide with aromatic amines was reported, the reaction was possibly carried out by opening of epoxide rings by amines, intramolecular cyclization and aromatization reactions.(4) In this paper , indium(III) chloride was found to be a highly effective catalyst for the three-component coupling reactions of aldehydes, alkynes, and amines (A³-coupling) via C-H activation. The reactions could be applied to both aromatic and aliphatic aldehydes and alkynes,nearly quantitative yields of the desired products were obtained in most cases, no co-catalyst or activator was required, and water was the only byproduct in the reactions. Furthermore, a tentative mechanism of the InCl₃-catalyzed one-pot, three-component coupling of aldehydes, alkynes, and amines were proposed.