Gold-catalyzed Rapid Construction of Nitrogen-containing Heterocyclic Compound Library with Scaffold Diversity and Molecular Complexity

1,3-unsubstituted 2-(1H-indol-2-yl)ethanamines were employed for the first time to react with alkynoic acids (AAs) to achieve gold-catalyzed highly selective cascade reactions to furnish novel indole-fused skeletons. Furthermore, with this powerful gold catalytic system, a library of indole/pyrrole/thiophene/benzene/naphthalene/pyridine-based nitrogen-containing heterocyclic compounds (NCHCs) with scaffold diversity and molecular complexity was constructed rapidly using various amine nucleophiles (ANs) and diverse AAs as the building blocks. This general protocol features excellent selectivity, extraordinarily broad substrate scope, readily available inputs, good to high yields, high bond-forming efficiency, and step economy, thus providing a facile and efficient access to a variety of valuable nitrogen-containing heterocycles.