Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, 1 Gehu Road, 213164, Changzhou, China.
Angew Chem Int Ed Engl. 2020 Dec 21;59(52):23516-23520. doi: 10.1002/anie.202009892. Epub 2020 Oct 19.
The asymmetric synthesis of β -amino acids remains a formidable challenge in organic synthesis. Here a novel organocatalytic enantioselective aminomethylation of ketenes with stable and readily available N,O-acetals is reported, providing β -amino esters bearing an all-carbon quaternary stereogenic center in high enantiomeric ratios with a catalytic amount of chiral phosphoric acid. Typically, this transformation probably proceeds through an asymmetric counter-anion-directed catalysis. As a result, a concise, practical, and atom-economic protocol toward rapidly access to β -amino acids has been developed.
β-氨基酸的不对称合成仍然是有机合成中的一个巨大挑战。在此，我们报道了一种新型的手性有机催化烯醇酮与稳定易得的 N,O-缩醛的对映选择性氨甲基化反应，在手性磷酸催化量的作用下，以高对映选择性得到了含有全碳季立体中心的β-氨基酯。通常，这种转化可能经过不对称的抗衡阴离子导向催化。因此，开发了一种简洁、实用、原子经济性的方法来快速获得β-氨基酸。
