Isocyanide-Based Multicomponent Bicyclization with Substituted Allenoate and Isatin: Synthesis of Unusual Spirooxindole Containing [5.5]-Fused Heterocycle.

A three-component bicyclization reaction of isocyanide, substituted allenoate, and isatin has been disclosed. This protocol is proposed to proceed through Michael addition, double cyclization, and [1,5]-hydride shift sequence, thus leading to the formation of two new rings and five new chemical bonds, including C-C, C-O, and C-N bonds.

Iron-Catalyzed Aerobic Oxidation and Annulation Reaction of Pyridine and α-Substituted Allenoate toward Functionalized Indolizine.

An iron-catalyzed reaction of pyridine and α-substituted allenoate has been disclosed. The present strategy incorporates the aerobic oxidation into annulation involving substituted allenoate, thus providing a new access to functionalized indolizine.