Iridium-Catalyzed Asymmetric Allylation of Silyl Enol Ethers Derived from α-Ketoesters and α-Diketones with Allylic Alcohols

We report an asymmetric allylation of silyl enol ethers derived from α-ketoesters with allylic alcohols by an iridium/chiral (P,olefin)-ligand catalyst. Allylation with a broad range of silyl enol ethers and allylic alcohols formed the allylated products with excellent enantioselectivities. Silyl enol ethers derived from α-diketones as well as α-ketoesters were also compatible with the asymmetric allylation to achieve nearly perfect enantioselectivities. The utility of allylated products bearing an α-ketoester group and an α-diketone group is demonstrated by transformation to valuable functional groups, exemplified by α-aminoester, aldehyde, 2(1H)-quinoxalinone, and quinoxaline.