Hybrid System of Metal/Brønsted Acid Relay Catalysis for the Intramolecular Double Hydroarylation and Cationic Cyclization of Diyne Diethers and Diamines

We have developed a hybrid system of metal/Brønsted acid relay catalysis for the intramolecular double hydroarylation and cationic cyclization of diyne diethers and diamines to give 4,4′-bi(2H-chromene), bi(2H-quinoline), and dioxafluoranthenes starting from 2,4-diyne-1,6-diethers and diamines in one reaction vessel under mild conditions.