Direct conjugate additions of a-carbonyl-stabilized nucleophiles to activated olefins are among the most attractive reactions for CÀC bond constructions owing to their ideal atom economy and the versatility of the activating functional groups involved. For catalytic asymmetric versions, a high level of efficiency has been demonstrated with 1,3-dicarbonylbased nucleophiles. [1] In contrast, the realization of a general, practical, highly active, and highly enantioselective catalyst for the conjugate addition of a-cyanoacetates to enones remains elusive. This might be explained by the fact that acyanoacetates are incapable of two-point binding to a Lewis acid. In this study we were particularly interested in the direct Michael addition of trisubstituted a-cyanoacetates to enones, in light of the demand for efficient catalytic asymmetric C À C bond-forming methods that create substituted quaternary stereocenters [2] and thus provide access to broadly useful multifunctional chiral building blocks. [3] Enolate formation by deprotonation of trisubstituted acyanoacetates with a Brønsted base such as a tertiary amine can trigger the conjugate addition to enones, [4] but the basic conditions might also induce various side reactions with basesensitive functionalities. To obtain synthetically useful enantioselectivities and yields, low-temperature reaction techniques, high catalyst loadings, and extended reaction times are usually required. In their seminal study in 1992, Ito and coworkers reported that a Rh I complex bearing a trans-chelating diphosphine ligand is able to catalyze the addition of acyanopropionate to vinyl ketones with high enantioselectivity in the absence of a base. [5] Unfortunately, a substituents bulkier than Me impeded valuable enantioselectivities. Subsequently, Richards et al. found that Pd II -pincer complexes
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