A highly regioselective synthesis of 1-n-methyl-spiro-[2,3′“]-oxindole-spiro-[3,2”]indane-1“, 3”-dione-4-arylpyrrolidines through 1,3-dipolar cycloaddition protocol

Abstract

2-Arylidene-1,3-indanediones undergo a regioselective 1,3-dipolar cycloaddition reaction with the azomethine ylide derived from isatin and sarcosine by decarboxylative route affording a series of 1-N-methyl — spiro[2.3′“]oxindole-spiro[3.2”]indane-1“,3”-diones-4-aryl pyrrolidines. The structures were established by spectroscopic techniques as well as single crystal X-ray analysis. Density functional theory at B3L YP/6-31G* and the semi empirical AM1 calculations were employed to rationalize the observed results. The experimental regioselectivity of 1,3-dipolar cycloadditions could be corroborated nicely with the computed Fukui frontier orbital energies and reaction energies.