2-aryl-4-azido-3-(bromo/iodo)quinolines as substrates for the synthesis of primary 4-amino-2,3-disubstituted quinoline derivatives

摘要

Staudinger reaction of the 2-aryl-4-azido-3-bromoquinolines and 2-aryl-4-azido-3-iodoquinolines with triphenyl phosphine in refluxing tetrahydrofuran afforded series of 2-aryl-3-halogeno-4-(triphenylphosphoranylideneamino)quinolines. The latter were, in turn, hydrolyzed to the corresponding primary 4-amino-2-aryl-3-(bromo/iodo)quinolines using 80% acetic acid under reflux. Tetrakis(triphenylphosphine)pal ladium(0)-catalyzed Suzuki reaction of the 2-aryl-3-iodo-4-(triphenylphosphoranylideneamino)quinolines with pheny)boronic acid in dimethyl formamide in the presence of 2 M K2CO3 followed by hydrolysis of the incipient 2,3-diaryl-4-(triphenylphosphoranylideneamino)quinolines with 80% acetic acid afforded the 4-amino-2,3-diarylquinolines.