A series of new nonsymmetric semi-azacrown ether ligands were developed and applied to the asymmetric Michael/cyclic keto-imine formation/Friedel–Crafts alkylation reactions of 3-amino oxindole hydrochlorides and β,γ-unsaturated α-keto amides. A diversity of 2,5-pyrrolidinyl dispirooxindoles containing two nonadjacent spiro-quaternary stereocenters were obtained in excellent diastereoselectivities
开发了一系列新的非对称半氮杂烷基醚
配体,并将其应用于3-
氨基羟
吲哚盐酸盐与β,γ-不饱和α-酮酰胺的不对称Michael /环状酮
亚胺形成/ Friedel-Crafts烷基化反应。以优异的非对映选择性和中等至出色的对映选择性(高达95%ee)获得了包含两个不相邻的螺-季四立体中心的2,5-
吡咯烷基二螺氧基辛多酮。提出了一个可能的催化循环来解释不对称感应的起源。