Asymmetric synthesis of γ-chiral borylalkanes sequential reduction/hydroboration using a single copper catalyst

The synthesis of γ-chiral borylalkanes through copper-catalyzed enantioselective S N 2′-reduction of γ,γ-disubstituted allylic substrates and subsequent hydroboration was reported. A copper-DTBM-Segphos catalyst produced a range of γ-chiral alkylboronates from easily accessible allylic acetate or benzoate with high enantioselectivities up to 99% ee. Furthermore, selective organic transformations of the resulting γ-chiral alkylboronates generated the corresponding γ-chiral alcohol, arene and amine compounds. Copper-catalyzed reductive hydroboration of γ,γ-disubstituted allylic substrates enables preparation of γ-chiral alkylboron compounds in a one-pot cascade manner.