We developed a copper-catalyzed three component reaction of aryl acetylene, enaminone and sulfonyl azide to construct iminolactone via copper-catalyzed alkyne–azide cycloaddition (CuAAC), Michael addition of metalated ketenimine followed by elimination and 6π electrocyclization.

α-Regio- and diastereoselective (3+2) cycloadditions of nitrone ylides derived from isatins with activated alkenes have been demonstrated. This mild protocol allows rapid access to a wide range of 3′,5′-diaryl-1′-hydroxy-2-oxospiro[indoline-3,2′-pyrrolidine] derivatives by using DABCO as an efficient catalyst. This method could also be carried out through three-component reaction efficiently in good yields and excellent diastereoselectivity.