Enantioselective Construction of α‐Chiral Silanes by Nickel‐Catalyzed C(sp
<sup>3</sup>
)−C(sp
<sup>3</sup>
) Cross‐Coupling
作者:Hong Yi、Wenbin Mao、Martin Oestreich
DOI:10.1002/anie.201814340
日期:2019.3.11
and yields α‐chiral silanes with high enantiocontrol. The catalyst system does not promote the cross‐coupling of the corresponding carbon analogue, corroborating the stabilizing effect of the silyl group on the alkyl radical intermediate (α‐silicon effect). Both coupling partners can be, but do not need to be, functionalized, and hence, even α‐chiral silanes with no functional group in direct proximity
报道了外消旋α-甲硅烷基化烷基碘与烷基锌试剂的对映选择性C(sp 3)-C(sp 3)交叉偶联。反应由NiCl 2 /(S,S)-Bn-Pybox并产生具有高对映体控制性的α-手性硅烷。催化剂体系不会促进相应碳类似物的交叉偶联,从而证实了甲硅烷基对烷基中间体的稳定作用(α-硅作用)。两个偶联伙伴都可以但不必进行官能化,因此,即使在不对称取代的碳原子直接附近没有官能团的α-手性硅烷也可以使用。这将新方法与已建立的合成α-手性硅烷的方法区分开来。