Cascade Reactions: A Multicomponent Approach to Functionalized Indane Derivatives by a Tandem Palladium-Catalyzed Carbamoylation / Carbocylization Process

A novel, multicomponent and stereoselective approach to functionalized indane derivatives is reported. It is based on a tandem process consisting of Pd-catalyzed oxidative carbamoylation of 2-(2-ethynylbenzyl)malonates with carbon monoxide, a secondary amine, and oxygen (with formation of a propiolamide intermediate), followed by carbocyclization, occurring through intramolecular addition of an in situ formed carbanion to the propiolamide moiety.