Tandem Michael addition/elimination – novel reactivity of pyridinium ylides in reaction with electron-deficient alkenes

Abstract

Novel reactivity of pyridinium ylides in reaction with annulated 4-oxothiazolidin-5-ylidenes as electron-deficient alkenes involving a cascade Michael addition/elimination process is described. The method provides a broad variety of functionalized products available from dipolarophiles with different substituents within the heterocyclic system as well as pyridinium salts with different electron-withdrawing groups (EWG = CO₂R, COPh, COMe, CN) in mild conditions with good to excellent yields.