Asymmetric O-methylhalohydrin reaction of chiral N-enoyl-2-oxazolidinones: synthesis of N-protected syn-β-methoxyphenylalanine, an unusual amino acid component of cyclomarins
作者:Saumen Hajra、Ananta Karmakar
DOI:10.1016/j.tetlet.2004.02.131
日期:2004.4
Asymmetric O-methylhalohydrin reactions of chiral N-enoyl-2-oxazolidinones were performed with halogens (Br2/I2) promoted by silver(I) in methanol with high regio- and anti-selectivity and moderate to good diastereoselectivity. Reagent-controlled opposite diastereoselectivity was observed especially for cinnamoyl and electron-deficient cinnamoyl substrates. This method was applied to the short enantioselective
手性N-烯丙基-2-恶唑烷酮类化合物的不对称O-甲基卤代醇反应是在甲醇中由银(I)促进的卤素(Br 2 / I 2)具有较高的区域选择性和抗选择性,并且具有中等至良好的非对映选择性。尤其是对于肉桂酰基和电子缺陷型肉桂酰基底物,观察到了试剂控制的相反非对映选择性。该方法用于N-保护的顺式-β-甲氧基苯基丙氨酸的短对映体选择性合成,这是环水杨酸的一种不常见的氨基酸成分。