Palladium-catalyzed and ligand-controlled divergent cycloadditions of vinylidenecyclopropane-diesters with para-quinone methides enabled by zwitterionic π-propargyl palladium species

A palladium-catalyzed divergent synthesis of spiro-cyclohexadienone with a five- or a six-membered ring by a cycloaddition reaction of vinylidenecyclopropane-diesters (VDCP-diesters) with p-quinone methides (p-QMs) was disclosed. This protocol features a...