First anti ‐Selective Direct Michael Addition of α‐Alkoxy Ketones to Enones by Cooperative Catalysis of Samarium(III) Trifluoromethanesulfonate and Tributyltin Methoxide

A new highly anti ‐diastereoselective Michael addition of α‐alkoxy ketones to α,β‐unsaturated ketones was achieved. This method features a dual‐catalyst protocol that combines samarium(III) trifluoromethanesulfonate and Bu 3 SnOMe. The combination of these two catalysts effectively allowed the generation of enolate species from α‐alkoxy ketones and produced Michael adducts in high yields with high anti diastereoselectivity. A variety of enones and α‐alkoxy ketones were applied to this system to give the anti products. One‐pot domino Michael/aldol reactions effectively afforded cyclic enones with a defined configuration.