Multicomponent One‐pot Diastereoselective Synthesis of Biologically Important Scaffold under Microwaves

A simple and fast three‐component diastereoselective synthesis of biologically important spiro scaffold 4 was carried out in reasonable purity starting from readily available 1H‐indole‐2,3‐dione 1, ethyl cyanoacetate 2 and 4‐hydroxycoumarin 3 under microwave in high yield (88%–92%) and short time.