In the presence of a catalytic amount of trityl salts, silyl enol ethers of thioesters react with α-substituted α,β-unsaturated cyclic ketones to afford the corresponding Michael adducts in good yields with excellent lk diastereoselectivities.
dyotropic rearrangement of α‐methylene‐β‐lactones has been realized, which enables the efficient access of a wide range of α‐methylene‐γ‐butyrolactones displaying remarkable structural diversity. Several appealing features of the reaction, including excellent efficiency, high stereospecificity, predictable chemoselectivity and broad substrate scope, render it a powerful tool for the synthesis of MBL‐containing