Design, Synthesis, and Application of Chiral C 2 -Symmetric Spiroketal-Containing Ligands in Transition-Metal Catalysis.

We present an expedient and economical route to a new spiroketal-based C-2-symmetric chiral scaffold, termed SPIROL. Based on this spirocyclic scaffold, several chiral ligands were generated. These ligands were successfully employed in an array of stereoselective transformations, including in iridium-catalyzed hydroarylations (up to 95% ee), palladium-catalyzed allylic alkylations (up to 97% ee), intermolecular palladium-catalyzed Heck couplings (up to 94% ee), and rhodium-catalyzed dehydroalanine hydrogenation (up to 93% ee).