Asymmetric Oxidative Dimerization of the Enolates of <i>N</i>-[Bis(methylthio)methylene]- and <i>N</i>-(Diphenylmethylene)glycine Esters
作者:Carlos Alvarez-Ibarra、Aurelio G. Csákÿ、Belén Colmenero、M. Luz Quiroga
DOI:10.1021/jo962116c
日期:1997.4.1
The oxidative dimerization of glycinates 1 with iodine takes place under kinetic control. The stereochemistry of the resulting 3-aminoaspartate 3 depends on the method used (base/solvent) to generate the corresponding enolate 2. Under suitable conditions, high yields and diastereomeric excesses in favor of the threo derivatives 3-I, which have C(2) symmetry, were obtained. In the presence of 8-phenylmenthol
甘氨酸盐1与碘的氧化二聚反应是在动力学控制下进行的。生成的3-氨基天冬氨酸3的立体化学取决于所用的方法(碱/溶剂),以生成相应的烯醇盐2。在合适的条件下,高收率和非对映体过量有利于苏式衍生物3-I,其具有C(2 )对称。在存在8-苯基薄荷醇作为手性助剂(2S,3S)-3-氨基天冬氨酸5-I的情况下。