Annelated 2-amino pyridines such as pyrrolo [2, 3-b] pyridines,[1, 8] naphthyridines, and pyrido [2, 3-b] azepines can be synthesized in moderate to good yields in a consecutive one- pot three-component process by a coupling-isomerization-enamine-addition- cyclocondensation sequence of an electron-poor (hetero) aryl halide, a terminal propargyl N- tosylamine, and an N, S-ketene acetal. After the coupling-isomerization sequence, a Diels ...
