C-H functionalization by high-valent CpCo(iii) catalysis

Significant progress has been accomplished in directed C-H functionalization through the use of earth-abundant and inexpensive first-row transition metals. Among these base metals, Co is especially attractive in view of its versatile applications in C-H functionalization, in both low- and high-valent states. In this vein, catalytic Co( iii ) species can be generated from the dissociation of a Cp*Co( iii ) catalyst or through the oxidation of a low-valent cobalt catalyst in the presence of an oxidant. In this feature article, we will discuss the breakthroughs in Cp*Co( iii )-promoted C-H functionalization. In this field, C(sp 2 )-H functionalization has been extensively studied and developed. In contrast, few C(sp 3 )-H functionalization reactions have been reported. Significant progress has been accomplished in directed C-H functionalization through the use of earth-abundant and inexpensive first-row transition metals.