Tetracyclic pyrrolidine/isoxazolidine fused pyrano [3, 2-h] quinolines were synthesized via intramolecular 1, 3-dipolar cycloaddition in ionic liquid. The transformations are operationally simple and environment-friendly in nature. The reaction is highly stereoselective affording exclusively the cis fused products, as deduced by the small coupling constant value (J= 4.8 Hz) between ring juncture protons which also showed ...
