Transition Metal-Catalyzed C(sp3)-C(sp3) Coupling to Construct All-Carbon Quaternary Carbon Centers

Abstract Transition-metal-catalyzed C(sp³)–C(sp³) cross-coupling reactions represent a powerful strategy for constructing all-carbon quaternary centers. However, these reactions remain challenging due to significant steric hindrance effects and the propensity for side reactions such as elimination and isomerization. This review provides a comprehensive summary of the progress made over the past few decades in the construction of all-carbon quaternary centers, with a focus on coupling reactions involving tertiary C(sp³) and primary/secondary C(sp³) centers [as the cross-coupling of two tertiary C(sp³) centers remains unsuccessful]. The discussion is organized around reaction conditions, substrate scope, and reaction mechanisms, and a brief overview of transformations based on these coupling reactions is also presented. 1 Introduction 2 3° C(sp3)–1° C(sp3) Cross-Coupling 2.1 Cobalt Catalysis 2.2 Copper Catalysis 2.3 Nickel Catalysis 2.4 Iron Catalysis 2.5 Other Catalysis 3 3° C(sp3)–2° C(sp3) Cross-Coupling 3.1 Copper Catalysis 3.2 Iron Catalysis 4 Conclusion