Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5218165 | Tetrahedron | 2012 | 8 Pages |
Abstract
Organocatalytic asymmetric conjugate addition of tert-butyl nitroacetates to β,γ-unsaturated α-keto esters has been developed. The subsequent in situ hydrolysis-decarboxylation of the adducts provided 5-nitro-2-oxopentanoates. A pyrrolidine-based thiourea-tertiary amine was identified as the best catalyst. A number of γ-aryl, γ-alkyl, and γ-heteroaryl β,γ-unsaturated α-keto esters and α-substituted tert-butyl nitroacetates were examined in the transformation. Generally 5-nitro-2-oxopentanoates were obtained in good yields (up to 97%) and enantioselectivities (up to 94% ee). The products were readily transformed to chiral proline derivatives by catalytic hydrogenation.
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Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Rui-jiong Lu, Wen-tao Wei, Jin-jia Wang, Shao-zhen Nie, Xue-jing Zhang, Ming Yan,