1531-62-0Relevant articles and documents
Improved ruthenium catalysts for the modified Friedlaender quinoline synthesis
Vander Mierde, Hans,Ledoux, Nele,Allaert, Bart,Van Der Voort, Pascal,Drozdzak, Renata,De Vos, Dirk,Verpoort, Francis
, p. 1572 - 1574 (2007)
Herein we describe an improved ruthenium catalyst for the oxidative cyclization of 2-aminobenzylalcohol with ketones, leading to quinolines via a modified Friedlaender synthesis. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Makisumi
, p. 1986,1988 (1965)
Highly enantioselective hydrogenation of quinolines using phosphine-free chiral cationic Ruthenium catalysts: Scope, mechanism, and origin of enantioselectivity
Wang, Tianli,Zhuo, Lian-Gang,Li, Zhiwei,Chen, Fei,Ding, Ziyuan,He, Yanmei,Fan, Qing-Hua,Xiang, Junfeng,Yu, Zhi-Xiang,Chan, Albert S. C.
supporting information; experimental part, p. 9878 - 9891 (2011/08/10)
Asymmetric hydrogenation of quinolines catalyzed by chiral cationic η6-arene-N-tosylethylenediamine-Ru(II) complexes have been investigated. A wide range of quinoline derivatives, including 2-alkylquinolines, 2-arylquinolines, and 2-functionalized and 2,3-disubstituted quinoline derivatives, were efficiently hydrogenated to give 1,2,3,4-tetrahydroquinolines with up to >99% ee and full conversions. This catalytic protocol is applicable to the gram-scale synthesis of some biologically active tetrahydroquinolines, such as (-)-angustureine, and 6-fluoro-2-methyl-1,2,3,4-tetrahydroquinoline, a key intermediate for the preparation of the antibacterial agent (S)-flumequine. The catalytic pathway of this reaction has been investigated in detail using a combination of stoichiometric reaction, intermediate characterization, and isotope labeling patterns. The evidence obtained from these experiments revealed that quinoline is reduced via an ionic and cascade reaction pathway, including 1,4-hydride addition, isomerization, and 1,2-hydride addition, and hydrogen addition undergoes a stepwise H+/H- transfer process outside the coordination sphere rather than a concerted mechanism. In addition, DFT calculations indicate that the enantioselectivity originates from the CH/π attraction between the η6-arene ligand in the Ru-complex and the fused phenyl ring of dihydroquinoline via a 10-membered ring transition state with the participation of TfO- anion.
Diels-Alder reaction of 1,2,3-benzotriazine with enamine: Application to the synthesis of alkaloids, 2-propylquinoline and 2-pentylquinoline
Koyama, Junko,Toyokuni, Izumi,Tagahara, Kiyoshi
, p. 332 - 334 (2007/10/03)
The Diels-Alder reaction of 1,2,3-benzotriazine with several pyrrolidine enamines of carbonyl compounds was carried out in chloroform in the presence of zinc bromide to afford 2- or 3-mono-, or 2,3-disubstituted quinolines. This method was applied to the synthesis of the alkaloids, 2-propylquinoline and 2-pentylquinoline.