We introduce 3-(alkoxycarbonyl-2-alkyliden)-2-oxindoles as pronucleophilic donors in the direct, vinylogous Michael addition to nitroolefins orchestrated by a chiral, bifunctional cinchona-thiourea organocatalyst. This reaction displays excellent levels of gamma-site-, diastereo- and enantioselectivity delivering valuable enantioenriched functionalized oxindoles. Of note, the C-gamma enolization of these pronucleophiles by the organocatalyst generates a multidentate, captodative dienolate that delivers vinylogous adducts with an unprecedented Z-selectivity through a peculiar interaction with the catalyst and the nitroolefin. The optimized procedure is operatively simple: the reaction is conducted in air, at room temperature, with low catalyst loading (up to 1mol%). The synthetic versatility of these Michael adducts is demonstrated by several transformations leading to a valuable quaternary oxindolyl proline analogue and a chiral spirocyclic furoindolone structure. Finally, a mechanistic rationale and a suitable transition state accounting for the observed selectivities are proposed, which are supported by DFT calculations.
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