We have disclosed a very nice advance of nickel(II)-catalyzed carboannulation reactions. Highly substituted indene derivatives are readily prepared in moderate to excellent yields under very mild reaction conditions in air via a nickel (II)-catalyzed cyclization of propargylic compounds with soft nucleophiles.
A new and efficient synthesis of 2-substituted indenes has been achieved via palladium-catalyzed carboannulation of propargylic carbonates with nucleophiles in good to excellent yields. A variety of nucleophiles were tolerated in this reaction.