One-Pot Synthesis of Pentasubstituted Pyridines following the Gold(I)-Catalyzed Aza-Enyne Metathesis/6 pi-Electrocyclization-Aromatization Sequence

The one-pot de novo synthesis of pentasubstituted pyridineswasrealized following the process of Au-(I)-autotandem catalysis and subsequentaromatization. The process involves aza-enyne metathesis witharyl propiolates to yield 1-azabutadienes and their addition/6 pi-electrocyclizationsequence with the other propiolate units. The resultant 1,4-dihydropyridineswere aromatized to furnish the pyridines in the presence of atmosphericoxygen. The aryl propiolates were regioselectively incorporated intothe ring system to afford 2-arylpyridines as the sole product.