Silyl-Group-Directed Linear-Selective Allylation of Carbonyl Compounds with Trisubstituted Allylboronates Using a Copper(I) Catalyst

A copper­(I)-catalyzed
linear-selective allylation of carbonyl compounds
with trisubstituted allylboronates has been achieved by capitalizing
on the electronic and steric effects of silyl groups. This reaction
provides stereodefined trisubstituted homoallyl alcohol derivatives
that bear a synthetically useful alkenyl silane moiety. The results
of a computational study suggested that the silyl directing group
thermodynamically stabilizes
the sterically hindered allylcopper­(I) intermediate and kinetically
facilitates the carbonyl allylation path for the linear product by
lowering the energy of its transition state.

通过充分利用硅基团的电子和立体效应，已实现铜(I)催化的羰基化合物与三取代烯丙基硼酸酯的线性选择性加成反应。该反应提供了具有合成上有用烯丙基硅烷基团的立体定义的三取代同分异构烯丙醇衍生物。一项计算研究表明，硅基导向基团在热力学上稳定了立体阻碍的烯丙基铜(I)中间体，并通过降低其过渡态的能量，动力学上促进了线性产物的羰基烯丙化路径。