Theoretical studies of regioselectivity of Ni- and Rh-catalyzed C–C bond forming reactions with unsymmetrical alkynes

This review highlights our theoretical studies of regioselectivities of Rh-catalyzed (5 + 2) cycloadditions, Ni-catalyzed reductive alkyne–aldehyde couplings, and Rh-catalyzed hydrogenative couplings of diynes and carbonyl partners. Factors that control the regioselectivities in these reactions are analyzed; these include steric repulsions involving the substrate and ligands, electronic effects dictated by metal–substrate interactions, and directing effects of conjugated alkenyl and alkynyl groups involving coordination to the metal.