Asymmetric Allylboration of α-Alkoxy-enones: Access to Enantioenriched Tertiary α-Hydroxy Ketones

We report an organocatalyzed asymmetric allylboration of α-alkoxy enones to access α-hydroxy enol ethers in yields up to 98% and up to 99% ee. These products can be subsequently transformed into a wide range of highly oxygenated products such as α-hydroxy ketones, α-hydroxy enones, and γ-hydroxy vinylogous esters. This methodology is also applicable to other α-heteroatom-containing ketones in analogous yield and ee (99% yield and 98% ee, respectively).