238. C.A. Falciola, K. Tissot-Croset, H. Reyneri, A. Alexakis,
     “β- and γ-disubstituted olefins: susbtrates for copper-catalysed asymmetric allylic substitution”
     Adv. Synth. Catal. 2008, 350, 1090-1100.

The copper-catalyzed asymmetric allylic alkylation has shown through many examples that it is a powerful means to generate stereogenic centers with mono β- and γ-substituted olefinic substrates. However, little has been reported about more substituted olefinic patterns, such as β-disubstituted allylic electrophiles. In this paper, we show that a simple procedure using easily accessible Grignard reagents and as low as 3 mol% of copper/ligand can promote high to nearly perfect enantioselectivities (up to >99% ee) with very good γ-selectivities on a wide panel of aliphatic or aromatic β-disubstituted substrates.

DOI : 10.1002/adsc.200800086 

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