Neighboring π‐Coordination in Palladium Catalyzed [4+4] Cycloaddition of γ‐Methylidene‐δ‐Valerolactones with Divinylketones

Abstract A palladium‐catalyzed [4+4] cycloaddition of aryl‐substituted γ‐methylidene‐δ‐valerolactones (GMDVs) with divinylketones (DVKs) was developed, providing an approach to access various mono‐cyclic tetrahydro‐2 H ‐oxocines with diverse substituents in 41% to 95% yield with 81:19 to >20:1 dr . This reaction was facilitated by anchoring olefin (C=C), carbonyl (C=O), and arene (Ar) at the α‐position of carbonyls.