Efficient synthesis of functionalized spiro[imidazolidine-2-thione-oxindoles] via catalyst-free domino Mannich cyclization

Abstract

An efficient protocol has been developed for the synthesis of spiro[imidazolidine-2-thioneoxindole] derivatives with multi-functionalized groups via catalyst-free domino reaction of by domino Mannich/cyclization of 3-isothiocyanato oxindoles and bis(arylmethylidene)hydrazines. The domino reaction can proceed smoothly in an environmentally benign conditions and provides pure functionalized spiro[imidazolidine-2-thione-oxindole] derivatives with excellent diastereoselectivity in moderate to excellent yield.