CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia.
J Org Chem. 2010 Nov 5;75(21):7365-72. doi: 10.1021/jo101600c.
The scope of a tandem conjugate addition-fluorination sequence performed on α,β-unsaturated esters using the enantiopure lithium amide derived from (S)-N-benzyl-N-(α-methylbenzyl)amine, and the electrophilic fluorinating agent N-fluorobenzenesulfonimide has been investigated. Using this method, α-fluoro-β(3)-amino esters can be obtained in up to quantitative yield and 80:20 to >99:1 dr. This simple methodology does not rely on the use of α-amino acids from the chiral pool and thus provides the potential for the preparation of enantiopure α-fluoro-β(3)-amino acids with a wide variety of side chains. Its utility was demonstrated through the synthesis of orthogonally protected (2S,3S)-α-fluoro-β(3)-lysine.
本文研究了使用（S）-N-苄基-N-（α-甲基苄基）胺衍生的手性锂酰胺和亲电氟化试剂 N-氟代苯磺酰亚胺对α，β-不饱和酯进行串联共轭加成-氟化反应的范围。使用这种方法，可以以高达定量产率和 80:20 至> 99:1 dr 的比例获得α-氟-β（3）-氨基酯。这种简单的方法不依赖于手性池中使用α-氨基酸，因此为制备具有广泛侧链的对映纯α-氟-β（3）-氨基酸提供了潜力。通过合成正交保护的（2S，3S）-α-氟-β（3）-赖氨酸证明了其用途。
