Gold-catalysed N-allenamide cyclisation as a platform for the construction of indole-fused quinoxaline and quinoline scaffolds

We report a gold-catalysed cyclisation of N-allenamides derived from 1- and 2-(2-aminoaryl)indoles, providing easy access to 5,6-dihydroindolo[1,2-a]quinoxalines and 6,11-dihydro-5H-indolo[3,2-c]quinolines. The reaction proceeds under mild conditions, tolerates diverse functional groups, and enables the synthesis of previously unexplored indole-fused heterocycles, whose versatility was demonstrated through selected post-functionalisation reactions.