An Update on Oxidative C–H Carbonylation with CO

Carbonyl derivatives widely exist in pharmaceuticals, agricultural chemicals, materials, and natural products. Developing novel, efficient, and green carbonylation methods represent one of the hottest research topics in organic synthesis, not only for academics but also for the chemical industry. Carbon monoxide (CO) turns out to be the most ideal carbonyl source because of its 100% atomic efficiency and low price. Meanwhile, compared with "classical" cross-coupling between nucleophiles and electrophiles, oxidative cross-coupling, which uses nucleophiles as reactants under oxidation conditions, has received increasing attention during the past two decades. Among oxidative carbonylation, the C–H functionalization/carbonylation is undoubtedly one of the most atom- and step-economical methods. Due to its great potential in green synthesis, this field has grown vigorously over the past decade, and many strategies have been developed, including transition metal catalysis, photoredox catalysis, electrochemical protocol, and so on. Since our last review of oxidative carbonylation in 2011, the C–H bond carbonylation has attracted continuous attention and undergone extensive development. Therefore, it is time to update this important field.