Stereoselective conjugate addition reactions of lithium amides to α,β-unsaturated chiral iron acyl complexes [(η5-C5H5)Fe(CO)(PPh3)(COCHCHR)]
作者:Stephen G. Davies、Jairton Dupont、Robert J.C. Easton、Osamu Ichihara、Jeffrey M. McKenna、Andrew D. Smith、José A.A. de Sousa
DOI:10.1016/j.jorganchem.2004.04.046
日期:2004.11
Conjugate addition of achiral lithium dimethylamide to the chiral iron cinnamoyl complexes (S,E)- and (S,Z)-[(η5-C5H5)Fe(CO)(PPh3)(COCHCHPh)] proceeds with high diastereoselectivity, with this protocol being used to establish unambiguously the absolute configuration of Winterstein’s acid (3-N,N-dimethylamino-3-phenylpropanoic acid) as (R). The highly diastereoselective conjugate addition of lithium
共轭加成的非手性二甲基氨基锂的手性铁络合物肉桂(小号,ë) -和(小号,Ž) - [(η 5 -C 5 H ^ 5)的Fe(CO)(PPH 3)(COCHCHPh)]进行以高非对映选择性,使用该方案可以明确地确定温特斯坦酸(3- N,N-二甲基氨基-3-苯基丙酸)的绝对构型为(R)。锂N-苄基-N的高度非对映选择性共轭加成-三甲基甲硅烷基酰胺形成一系列α,β-不饱和铁酰基络合物,然后通过烷基化或醛醇缩合反应原位合成衍生的烯酸酯,这也促进了顺式和反式-β-内酰胺的立体选择性合成。该方法已被用于实现(±)-橄榄酸和(±)-硫霉素的形式不对称合成。手性氨基化锂的添加来自伯和仲胺衍生的铁巴豆络合物[(η 5 -C 5 H ^ 5)的Fe(CO)(PPH 3)(COCHCHMe)]表示锂Ñ -α-甲基苄显示低水平的对映体识别,而锂N-3,4-二甲氧基苄Ñ -α-甲基苄基酰胺和锂Ñ苄基Ñ -α-甲基苄