Synthesis of Spiroaminals and Spiroketals with Bimetallic Relay Catalysis

A novel tandem metal relay catalytic system was developed by combining gold-catalyzed cycloisomerization with an early transition-metal-catalyzed inverse-electron-demand hetero-Diels–Alder (IED-HDA) reaction. Various biologically important spiroaminals and spiroketals were obtained with very high efficiency under mild conditions