Palladium-catalyzed intramolecular alkyne-carbon monoxide-alkene insertion cascade for synthesis of .alpha.-methylenecyclopentenones
摘要:
A method for the construction of alpha-methylenecyclopentenones fused to five-membered rings using a palladium catalyst is reported. The procedure involves the formation of pi-allylpalladium intermediates that undergo sequential intramolecular alkyne insertion, carbon monoxide insertion, intramolecular alkene insertion, and beta-hydride elimination. Examples of the cyclization are seen in eq 2 and Scheme III.
Metal-catalyzed organic photoreactions. Bond-cleavage selectivity and synthetic application of the iron(III) chloride catalyzed photooxidation of cyclic olefins