Catalytic asymmetric protonation of lithium enolates using amino acid derivatives as chiral proton sources
Catalytic asymmetric protonation of lithium enolates using amino acid derivatives as chiral proton sources
复制标题
DOI：
10.1021/ol0603007
复制
发表时间：
2006-04-13
期刊：
影响因子：
5.2
通讯作者：
Yanagisawa, A
中科院分区：
文献类型：
--
作者：
Mitsuhashi, K;Ito, R;Yanagisawa, A
以市售氨基酸衍生物作为手性质子源，研究了锂的不对称质子化反应。在所测试的氨基酸衍生物中，N-β-L-天冬氨酸-L-苯丙氨酸甲酯在烯醇酸锂的质子化反应中具有显著的不对称诱导作用。在催化量的手性质子源存在下得到的产物的对映体过量(高达88%ee)高于在化学计量反应中得到的产物。
Asymmetric protonation of lithium enolates was examined using commercially available amino acid derivatives as chiral proton sources. Among the amino acid derivatives tested, N beta-L-aspartyl-L-phenylalanine methyl ester was found to cause significant asymmetric induction in the protonation of lithium enolates. The enantiomeric excess (up to 88% ee) of the products obtained in the presence of a catalytic amount of the chiral proton source was higher than those obtained in the stoichiometric reaction.