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The success in the identification of the two enantioisomeric surfaces of electrophiles by dinuclear zinc catalysts is disclosed. This protocol realizes a dinuclear zinc‐cocatalyzed desymmetrization of cyclopentendiones using α‐hydroxy aryl ketones as nucleophiles through Michael addition reaction. Under mild conditions, a series of functional cyclopentanediones bearing multiple stereogenic centers including an all‐carbon quaternary stereocenter, were obtained in moderate to good yields with excellent stereoselectivities. [ABSTRACT FROM AUTHOR]

An efficient approach to saccharin‐fused 1,4‐DHPs has been established by using a [3+3] annulation process. The chemical event was enabled by a Et3N‐catalyzed tandem Michael/aza‐Pinner reaction of alkyl cyclic N‐sulfonyl ketimines as nucleophiles with α,α‐dicyanoolefins. Under mild conditions, the desired products were readily prepared in good to excellent yields and with broad functional group tolerance (up to 95 % yield, 29 examples). Notably, this practical methodology features the synthesis of pentacyclic spirooxindoles bearing a quaternary spiro‐stereocenter. [ABSTRACT FROM AUTHOR]