The active complexes of chiral N,N′‐dioxide ligands with dysprosium and magnesium salts catalyze the hetero‐Diels–Alder reaction between 2‐aza‐3‐silyloxy‐butadienes and alkylidene oxindoles to selectively form 3,3′‐ and 3,4′‐piperidinoyl spirooxindoles, respectively, in very high yields and with excellent enantioselectivities. The exo‐selective asymmetric cycloaddition successfully regaled the construction
手性N,N'-二氧化物
配体与和
镁盐的活性络合物催化2-氮杂-3-甲
硅烷基氧基
丁二烯与亚烷基氧
吲哚之间的杂狄尔斯-阿尔德反应,选择性地形成3,3'-和3,4分别以非常高的收率和极好的对映选择性来合成'-
哌啶子基螺
硫辛多酯。所述外切-选择性环加成不对称成功款待
SP的结构3富和高度取代的基于
天然产物SPirooxindoles支撑许多手性中心,包括连续的全碳季中心。