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
An Improved Environmentally Friendly Approach to 4-Nitro-, 4-Sulfonyl-, and 4-Aminoquinolines and 4-Quinolones through Conjugate Addition of Nucleophiles to β-(2-Aminophenyl)-α,β-ynones
led to valuable 4-sulfonylquinolines and 4-nitroquinolines. The latter proved to be versatile precursors of N-unsubstituted 4-aminoquinolines and 4-quinolones. Reaction of β-(2-aminophenyl)-α,β-ynones with DMF/NaOH resulted in the formation of 4-(dimethylamino)quinolines. The use of an alternative CO-free procedure for the preparation of substrates β-(2-aminophenyl)-α,β-ynones allowed extension of the
Gold-Catalyzed Synthesis of Dibenzo[1,5]diazocines from β-(2-Aminophenyl)-α,β-ynones
作者:Navnath D. Rode、Antonio Arcadi、Marco Chiarini、Fabio Marinelli、Gustavo Portalone
DOI:10.1002/adsc.201700694
日期:2017.10.4
means of (JonPhosAuNCMe)SbF6 catalysis. In contrast with the known gold-catalyzed reaction path of 2-alkynylanilines that leads to indoles, ynones underwent an auto intermolecularhydroamination. This process resulted finally in the formation of an eight-membered ring, likely through a selective 8-exo-dig intramolecular hydroamination that prevailed over the possible cyclocondensation reaction (that
with nitrogennucleophiles to give three major types of products, depending on reaction conditions and variation in the nucleophiles. The reaction may lead to simple 1,2-nucleophilic adducts or, at higher temperatures, to a divergent sequential cyclisation giving rise to 2-aryl-4-aminoquinolines by reaction with amines, or to substituted 2-aryl or 2-alkyl-4-alkylidene quinazolines by reaction with