Furthermore, the competition kinetics experiments were repeated at varying Ni loadings. No dependence on the ratio of A:B and catalyst loading was found, again indicative of a caged, innersphere radical rebound mechanism (Figure ). Altogether, these mechanistic analyses find that stereoretention is possible through an inner-sphere radical cross-coupling mechanism which circumvents the thermodynamic challenges typically assocated with C(sp 2 )-C(sp 3 ) bond formation from Ni(II).