Subscribe to RSS
DOI: 10.1055/s-0033-1340455
N,N′-Dioxide–Scandium(III)-Catalyzed Asymmetric Michael Addition
Publication History
Publication Date:
13 December 2013 (online)
Key words
α,β-unsaturated γ-keto esters - γ-butenolides - N,N′-dioxides - Michael addition - scandium
Significance
Butenolide derivatives represent an important structural motif in natural products and pharmaceuticals. The authors develop a highly efficient catalytic system for the asymmetric vinylogous Michael addition of γ-substituted butenolides to α,β-unsaturated γ-keto esters, leading to γ,γ-disubstituted butenolides in good yield and excellent enantioselectivities.
#
Comment
The substrate scope of this reaction is well investigated. The ester groups of the α,β-unsaturated γ-keto esters display an influence on both diastereo- and enantioselectivity. The bulkier γ-substituted groups in the butenolides lead to the increase of diastereo- and enantioselectivity, but the reactivities decrease obviously. Aromatic and aliphatic unsaturated γ-keto esters are well tolerated.
#
#
