Cooperative Gold(I)/DMAP Catalysis Enabled (2 + 3) Cycloadditions of Yne–Enones with Oxindole-Derived MBH Carbonates

A cooperative
gold(I)/DMAP system catalyzes the (2 + 3) cycloadditions
of yne–enones with oxindole-derived Morita–Baylis–Hillman
(MBH) carbonates, yielding diverse bispiro-cyclopentene oxindole products.
The mild, scalable protocol demonstrates broad substrate scope and
excellent chemo- and diastereoselectivity. Mechanistic study reveals
pivotal roles of both catalysts in the unique (2 + 3) cycloaddition.
This strategy showcases superiority in achieving transformation with
unique chemoselectivity and excellent diastereoselectivity, unattainable
through traditional monocatalytic methodologies.