Multicomponent Synthesis of Heteroaryl‐Annulated Spirocarbazoles

ABSTRACT A series of dispirooxindole‐pyrrolidine/pyrrolizidine derivatives was synthesized in a dioxane‐methanol mixture under reflux via a 1,3‐dipolar cycloaddition reaction between an azomethine ylide and various 2‐heteroarylidene‐2,3,4,9‐tetrahydrocarbazol‐1‐ones. The structures of the resulting compounds were confirmed through spectroscopic methods (FT‐IR, 1 H‐NMR, and 13 C‐NMR) and single‐crystal x‐ray diffraction analysis. This convergent method demonstrates good generality and functional group tolerance, simplifying both traditional and modern synthetic strategies. The protocol offers advantages such as straightforward workup procedures, higher yields, shorter reaction times, and an environmentally friendly nature. X‐ray diffraction analysis also elucidated the stereochemistry and regiochemistry of the spirocyclic adducts.