K₂CO₃ Promoted Spirocyclopropanation of Thiazole‐Derived Oxadienes via 1,4‐Addition‐Induced Dearomatization Reaction

AbstractA K2CO3 promoted spirocyclopropanation of thiazole‐derived oxadienes with bromomalonate via 1, 4‐addition‐induced dearomatization strategy has been developed. The pathway features a broad substrate scope, operational simplicity and high degree of synthetic efficiency to afford series of functionalized spiro‐cyclopropanation frameworks in 88 %–96 % yields, which enriches the research contents of thiazole‐derived oxadienes involved reactions. All products obtained herein contain two contiguous quaternary centers and their further synthetic applications are also demonstrated.