Co-catalyzed C–C Coupling Reactions with Csp² Electrophiles

Transition metal-catalyzed formation of C–C bonds was one of the most important methods in chemical synthesis since the pioneering work of Heck, Negishi, and Suzuki. Now, cross-coupling reactions involving Csp² electrophiles are commonplace in both industrial and academic research. With the development in this field, cheap and less toxicologically benign cobalt catalyst attracted more and more attention, and displays a high catalytic activity in many cases and a low tendency to produce homocoupling and β-elimination by-products. In this chapter, we will introduce the Co-catalyzed cross-coupling of Csp² electrophiles with organometallic reagents (like Grignard reagent, organozinc, organoboron, etc.) to construct Csp²–C bonds, as well as the Co-catalyzed reductive cross-couplings involving two electrophiles.