Dynamic Kinetic Asymmetric Transformations of β-Stereogenic α-Ketoesters by Direct Aldolization
نویسندگان
چکیده
منابع مشابه
Dynamic Kinetic Asymmetric Cross-Benzoin Additions of β-Stereogenic α-Keto Esters
The dynamic kinetic resolution of β-halo α-keto esters via an asymmetric cross-benzoin reaction is described. A chiral N-heterocyclic carbene catalyzes the umpolung addition of aldehydes to racemic α-keto esters. The resulting fully substituted β-halo glycolic ester products are obtained with high levels of enantio- and diastereocontrol. The high chemoselectivity observed is a result of greater...
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Biocatalytic procedures can circumvent some of the drawbacks that classical methodologies present in chemical synthesis. One example is shown by the Baeyer-Villiger (BV) reaction, a process discovered more than 100 years ago that consists in the nucleophilic insertion of one atom of oxygen in the adjacent position of a carbonyl moiety affording esters or lactones. This reaction proceeds using p...
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Asymmetric Michael addition of 1-acetylindolin-3-ones to β,γ-unsaturated α-ketoesters was investigated for the synthesis of chiral indolin-3-ones with two adjacent tertiary stereogenic centers. Under the catalysis of a chiral bifunctional squaramide derived from l-tert-leucine, a wide range of 1-acetylindolin-3-ones and β,γ-unsaturated α-ketoesters were well-tolerated in this transformation to ...
متن کاملEnantioselective γ-Alkylation of α,β-Unsaturated Malonates and Ketoesters by a Sequential Ir-Catalyzed Asymmetric Allylic Alkylation/Cope Rearrangement.
A catalytic, enantioselective γ-alkylation of α,β-unsaturated malonates and ketoesters is reported. This strategy entails a highly regio- and enantioselective iridium-catalyzed α-alkylation of an extended enolate, and a subsequent translocation of chirality to the γ-position via a Cope rearrangement.
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ژورنال
عنوان ژورنال: Angewandte Chemie International Edition
سال: 2013
ISSN: 1433-7851
DOI: 10.1002/anie.201306873