Gold-Catalyzed Highly Diastereoselective Synthesis of Functionalized 3,4-Disubstituted Butyrolactams via Phosphatyloxy or Carbonate Double Migrations

A gold-catalyzed highly diastereoselective synthesis of functionalised 3,4-disubstituted butyrolactams via phosphatyloxy or carbonate double migrations is reported, which is proposed to proceed by a tandem 1,3-phosphatyloxy or carbonate migration and a long-range 1,5-phosphatyloxy or carbonate migration, which overall corresponds to a formal 1,6-migration.