One‐pot Regioselective Synthesis of Novel 1‐ N ‐Methyl‐spiro[2,3′]oxindole‐spiro[3,3″]‐1″‐ N ‐arylpyrrolidine‐2″,5″‐dione‐4‐arylpyrrolidines through Multicomponent 1,3‐Dipolar Cycloaddition Reaction of Azomethine Ylide

An atom economic and facile synthesis of novel dispiro–oxindole–pyrrolidines has been achieved via a three‐component tandem cycloaddition of azomethine ylide generated in situ from isatin and sarcosine by decarboxylative condensation with N ‐aryl‐3‐benzylidene‐pyrrolidine‐2,5‐dione derivatives as dipolarophiles. The salient features of synthetic procedure are characterized by the mild reaction conditions, high yields, high regioselectivity and stereoselectivity, one‐pot procedure , and operational simplicity. This regioselectivity was assumed to be under the influence of π–π stacking interactions between the aromatic rings of azomethine ylide and N ‐aryl‐3‐benzylidene‐pyrrolidine‐2,5‐diones that further control the exo–endo selectivity of the reaction 1,3‐dipolar cycloaddition . The regiochemistry and structures of the cycloadducts were determined with spectroscopic data.