Four‐Component Regio‐ and Diastereoselective Synthesis of Pyrrolizidines Incorporating Spiro‐Oxindole/Indanedione via 1,3‐Dipolar Cycloaddition Reaction of Azomethine Ylides

The present investigation reports an easy regio‐ and diastereoselective access to a library of diverse polycyclic pyrrolizidine fused spiro‐1,3‐indandione/oxindole derivatives through a one‐pot sequential four‐component reactions of 4‐oxo‐4 H ‐chromene‐3‐carbaldehyde/2‐chloroquinoline‐3‐carbaldehyde, 1‐phenyl‐2‐(1,1,1‐triphenyl‐ λ 5 ‐phosphanylidene)ethan‐1‐one, ninhydrin or isatin, and L‐proline in EtOH at room temperature. This protocol features excellent chemical yields, high diastereoselectivity and operational simplicity.