Gold-catalyzed intermolecular annulations using alkynes as two-carbon synthons for the construction of aromatic and non-aromatic ring systems

Abstract

Gold-catalyzed intermolecular annulations employing alkynes as two-carbon synthons provide a powerful strategy for the modular construction of both aromatic and non-aromatic ring systems. These transformations typically proceed under mild conditions with high selectivity, enabling efficient and predictable access to a broad range of complex heterocycles, including pyrroles, indoles, quinolines, carbazoles, furans, oxazoles, and other azole derivatives, as well as saturated and partially unsaturated heterocycles such as dihydrofurans, and tetrahydropyridine frameworks. This Feature Article summarizes and reviews the representative work in this flourishing field, with emphasis on reaction design, mechanistic insights, and selectivity control, and highlights the broad synthetic potential of these processes. Despite significant advances, challenges remain, particularly the limited number of asymmetric variants and the underexplored non-aromatic scaffolds, highlighting opportunities for further development.