By reacting a β-hydroxy-α-amino acid with sulfuryl fluoride (SO2F2) in the presence of an organic base, it is possible to produce an α-fluoro-β-amino acid of the formula [2].
By using a C8-12 tertiary amine having two or more alkyl groups of C3 or higher, and especially diisopropylethylamine, as the organic base, by-production of quantery ammonium salts is effectively suppressed. By applying the production process of the present invention, it is possible to very easily produce
(2R)-3-(dibenzylamino)-2-fluoropropionic acid methyl ester, which is extremely important as a pharmaceutical intermediate, with high positional selectivity even on an industrial scale.
在有机碱存在下,β-羟基-
α-氨基酸与
氟化
硫(SO2F2)反应,可以生成式[2]的α-
氟-β-
氨基酸。
使用具有两个或两个以上 C3 或更高烷基的 C8-12 叔胺,特别是
二异丙基乙胺作为有机碱,可有效抑制季
铵盐的副产物。采用本发明的生产工艺,可以非常容易地生产出
(2R)-3-(二苄基
氨基)-
2-氟丙酸甲酯,它作为一种极其重要的医药中间体,即使在工业规模上也具有很高的位置选择性。