The development of the sequential Corey-Chaykovsky reactions of isatins, spiroepoxy-, or spiroaziridine oxindoles with sulfur ylide has led to the discovery of a unique reaction mode that allows easy and direct one-pot access to a range of spirocyclopropyl oxindoles.

The first feedback inhibition, similar to enzyme catalysis, in the Co­(III)­salen-catalyzed asymmetric ring-opening reaction of N-free spiro-epoxyoxyindole has been discovered, which leads dynamic kinetic to kinetic resolution. This is the first report of the enantioselective construction of all carbon quaternary center from any epoxide employing metal–salen catalyst until date. This protocol provides an easy access of 3-(3- indolyl)­oxindole methanols, a privileged building block for the synthesis of a large variety of 3,3′-bisindole alkaloids.

Metal triflate-catalysed intermolecular Friedel-Crafts reactions involving electron-rich benzenoid arenes and spiroepoxyoxindoles at the spiro-centre have been developed for the exclusive regioselective synthesis of 3-aryl-(3-hydroxymethyl)oxindoles with an all-carbon quaternary centre. Selective ringo pening of spiroepoxyoxindoles with phenols provided ad irect access to 3-(hydroxymethyl)-3-(2-hydroxyaryl)oxindoles.W eh ave utilized this methodologys uccessfully as the key step for the synthesis of benzofuroindolinesa nd 2H-spiro[benzofuran]-3,3'-oxindoles.