4292-00-6Relevant academic research and scientific papers
β- and γ-disubstituted olefins: Substrates for copper-catalyzed asymmetric allylic substitution
Falciola, Caroline A.,Tissot-Croset, Karine,Reyneri, Hugo,Alexakis, Alexandre
supporting information; scheme or table, p. 1090 - 1100 (2009/05/30)
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.
β-disubstituted allylic chlorides: Substrates for the Cu-catalyzed asymmetric SN2′ reaction
Falciola, Caroline A.,Tissot-Croset, Karine,Alexakis, Alexandre
, p. 5995 - 5998 (2007/10/03)
Scope broadened: A previously developed asymmetric Cu-catalyzed allylic substitution can be applied to more substituted allylic patterns. Two classes of β-disubstituted substrates, cinnamyl derivatives and aliphatic endocyclic allylic chlorides, afford excellent regio- and enantioselectivities (see schemes; L* = phosphoramidite ligand). (Chemical Equation Presented).
