The combination of Pd(TFA)2 and an N,N′-disulfonyl bisimidazoline ligand shows high catalytic activity and excellent asymmetric induction in the addition of arylboronic acids to cyclic N-sulfonyl ketimines including benzo[d]isothiazole-1,1-dioxides, benzo[e][1,2,3]oxathiazine-2,2-dioxides, and 1,2,5-thiadiazole-1,1-dioxides, by which three types of chiral quaternary carbon-containing sultams with substantial
Pd(TFA)2和N,N'-二磺酰基双咪唑啉配体的组合显示出高催化活性和出色的不对称诱导作用,这是因为将芳基硼酸添加到环状N-磺酰基酮亚胺中,包括苯并[ d ]异噻唑-1,1-二氧化物苯并[ e] [1,2,3]草噻嗪-2,2-二氧化物和1,2,5-噻二唑-1,1-二氧化物,可合成具有高取代多样性的三种类型的手性含季碳的均二产率高,对映选择性高(ee> 99%)。当前的催化表现出对氧气的显着耐受性,因此为构建对映体富集的环状四元立体中心提供了一种操作简单的方法。