Design, Synthesis, and Application of Chiral C2 -Symmetric Spiroketal-Containing Ligands in Transition-Metal Catalysis.

Abstract

We present an expedient and economical route to a new spiroketal-based C2 -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).