Abstract
Extensive investigations of chiral auxiliaries and active metals for Michael addition of 1,3‐dicarbonyl compounds with vinyl ketones are summarized. Our efforts result in a widely applicable auxiliary‐mediated, copper(II) acetate‐catalyzed procedure. For these purposes, L‐valine diethylamide is an optimal chiral auxiliary giving quaternary stereocenters with up to 99 % ee at ambient temperature. No inert or anhydrous conditions are required, the solvent is simply acetone, and the auxiliary can be recovered almost quantitatively after workup.

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