Catalytic Asymmetric Synthesis of Aromatic Spiroketals by SpinPhox/Iridium(I)-Catalyzed Hydrogenation and Spiroketalization of α,α′-Bis(2-hydroxyarylidene) Ketones
From spiro to spiro: An iridium(I) complex with a spiral P,N ligand (SpinPhox) is highly efficient in the catalytic asymmetric hydrogenation of α,α′‐bis(2‐hydroxyarylidene) ketones to afford the corresponding aromatic spiroketals in high yields with excellent diastereo‐ and enantioselectivities (see scheme). The complex plays a dualrole in the reaction, acting as catalyst for both the hydrogenation