Transition-metal-catalyzed coupling reactions have become a versatile tool for chemical bond formation. From the variation of the coupling partners, coupling reactions can be classified into three models: traditional coupling, reductive coupling and oxidative coupling. The oxidative coupling, which is different from the traditional coupling, occurs between two nucleophiles. This critical review focuses on transition-metal-catalyzed oxidative coupling reactions involving organometallic reagents as nucleophiles. Since the scope of the oxidative coupling is highly diversified, this paper only reviews the oxidative coupling reactions concerning C-C bond formation, including the coupling between organometal reagents and hydrocarbons as well as coupling between two organometal reagents. Since terminal alkynes are normally activated by metal salts and in situ form the alkynyl metal reagents in coupling reactions, they are directly considered as organometal reagents in this review. Intramolecular oxidative couplings and oxidative cyclizations are not included in this critical review. Moreover, there are many examples of oxidative coupling leading to the formation of functional materials, such as the oxidative polymerization of thiophenes. Since several reviews in these areas have been published they are not included in this review either (99 references).

The first copper-catalysed oxidative alkenylation of simple ethers to construct allylic ethers was successfully achieved. Different substituted olefins and simple ethers could be cross-coupled well to generate the corresponding alkenylation products. Notably, open-chain ethers were also found to be efficient coupling partners in this reaction. This reaction is likely to proceed via a radical process.

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Controlling selectivity is of central importance to radical chemistry. However, the highly reactive and unstable radical intermediates make this task especially challenging. Herein, a strategy for taming radical redox reactions has been developed, in which solvent-bonding can alter the reactivity of the generated radical intermediates and thereby drastically alter the reaction selectivity at room temperature. Various β-oxy sulfoxides and β-hydroxy sulfides can be facilely obtained, some of which are difficult to synthesize by existing methods. Notably, neither a metal catalyst nor any further additives are necessary in these processes.