Au-catalyzed synthesis of 2-alkylindoles from N-arylhydroxylamines and terminal alkynes

The first gold-catalyzed addition of N-arylhydroxylamines to aliphatic terminal alkynes is developed to access O-alkenyl-N-arylhydroxylamines, which undergo facile in situ sequential 3,3-rearrangements and cyclodehydrations to afford 2-alkylindoles with regiospecificity and under exceptionally mild reaction conditions.