Sequential 1,3-Dipolar Cycloaddition of Nitrones to β-(2-Aminophenyl) α,β-Ynones and Cyclocondensation: A New Entry to the Isoxazolino[4,5-c]quinoline Ring
Gold-Catalyzed Cascade Reaction of β-(2-Aminophenyl)-α,β-ynones with Ynamides: A Sequential Route to Polysubstituted 2-Aminoquinolines
作者:Navnath D. Rode、Antonio Arcadi、Antonella Di Nicola、Fabio Marinelli、Véronique Michelet
DOI:10.1021/acs.orglett.8b01928
日期:2018.9.7
A novel, efficient, and mild synthetic route for the preparation of 2-aminoquinolines via a gold-catalyzed cascade reaction of β-(2-aminophenyl)-α,β-ynones with ynamides has been developed. This process tolerates a wide range of functionalities such as halogen, alkyl, aryl, and heteroaryl groups, leading to original heterocycles in fair to very good yields.
An operationally simple procedure, involving conjugate addition of NaI to β-(2-aminophenyl)-α,β-ynones/cyclization/Pd-catalyzed reaction with 2-alkynyl-trifluoroacetanilides, afforded 4-(1H-indol-3-yl)quinolines. The whole process was carried out in the same flask, without any intermediate work-up and using ethanol as solvent. annulation - palladium - quinolines - indoles - heterocycles - one-pot reaction