Gold-catalyzed intramolecular cyclization/condensation sequence: synthesis of 1,2-dihydro[c][2,7]naphthyridines.

An efficient gold-catalyzed synthetic protocol for the construction of 1,2-dihydro[c][2,7]naphthyridines from 2-aminophenyl prop-2-yn-1-yl enaminones has been developed. In this organic transformation new C-C and C-N bond formations occur via 6-endo-dig cyclization and condensation. 1,2-Dihydro[c][2,7]naphthyridine derivatives were obtained in good to excellent yields in a one-pot synthesis at ambient temperature.