Asymmetric α-amination of β-keto esters using a guanidine–bisurea bifunctional organocatalyst
نویسندگان
چکیده
An asymmetric α-amination of β-keto esters with azodicarboxylate in the presence of a guanidine-bisurea bifunctional organocatalyst was investigated. The α-amination products were obtained in up to 99% yield with up to 94% ee.
منابع مشابه
Development of Guanidine-Bisurea Bifunctional Organocatalysts with a Chiral Pyrrolidine Moiety and Application to α-Hydroxylation of Tetralone-Derived β-Keto Esters.
Novel guanidine-bisurea bifunctional organocatalysts 5 bearing a chiral pyrrolidine moiety on guanidine were designed with the guidance of DFT calculations. The resulting organocatalysts 5 were examined for α-hydroxylation of tetralone-derived β-keto esters, and good selectivity was obtained with 5j bearing a methoxymethyl ether-containing chiral pyrrolidine moiety.
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