glyoxylates and β-lactones to give highly functionalized Claisen condensation products. A heretofore undocumented instance of stereochemical 1,4-induction results in efficient transmission of β-lactone stereochemistry to the emerging fully substituted stereocenter. Second-stage transformations reveal that the five heteroatom-containing functionalities embedded within the products are entirely chemo-differentiated
Reformatsky 试剂依次与
乙醛酸甲
硅烷基
酯和 β-内
酯反应,得到高度官能化的克莱森缩合产物。迄今为止未记录的立体
化学 1,4-诱导实例导致 β-内
酯立体
化学有效传输到新兴的完全取代的立体中心。第二阶段的转化表明,嵌入产品中的五个含杂原子的功能是完全
化学分化的,这种情况允许快速组装 leustroducsin B 核心亚结构。