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 - 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.