Control of Axial Chirality through NiH-Catalyzed Atroposelective Hydrofunctionalization of Alkynes

Catalytic asymmetric hydrofunctionalization
of alkenes is a well-established
method with which to construct complex C(sp3)-enriched
molecules with central chirality. In contrast, the use of catalytic
asymmetric hydrofunctionalization of abundant alkyne substrates to
produce valuable multisubstituted alkenes with axial chirality remains
largely unexplored. Here, we report a general procedure of this type
catalyzed by abundant Ni(II) salts and employing a structurally simple
chiral PyrOx ligand. A wide variety of structurally diverse atropisomeric
chiral styrenes have been obtained from hydroarylation of alkynes
with high efficiency, complete Z-selectivity, and
excellent enantioselectivity.