Practical Synthesis of Natural
Amino Acid Derivatives: Hf(OTf)<sub>4</sub>-Catalyzed Mannich-Type
Reaction of Ketene Silyl Acetals or Enol Silyl Ethers with <i>N</i>,<i>O</i>-Acetals
as a Glycine Cation Equivalent
作者:Norio Sakai、Asuka Sato、Takeo Konakahara
DOI:10.1055/s-0029-1216743
日期:——
The authors demonstrated the Hf(OTf) 4 -catalyzed Mannich-type reaction of an enol silyl ether and a ketene silyl acetal with an N,O-acetat leading to the preparation of amino acid derivatives. In particular, use of the N,O-acetal having a bis(trimethylsilyl)amino group directly produced N-unprotected aspartic acid derivatives after a standard aqueous workup.
作者展示了 Hf(OTf) 4 催化的烯醇甲
硅烷基醚和烯酮甲
硅烷基
缩醛与 N,O-
乙酸酯的曼尼希型反应,导致制备
氨基酸衍
生物。特别是,使用具有双(三甲基甲
硅烷基)
氨基的 N,O-
缩醛在标准
水处理后直接产生了 N-未保护的
天冬氨酸衍
生物。