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 Csp(2) 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 beta-elimination by-products. In this chapter, we will introduce the Co-catalyzed cross-coupling of Csp(2) electrophiles with organometallic reagents (like Grignard reagent, organozinc, organoboron, etc.) to construct Csp(2)-C bonds, as well as the Co-catalyzed reductive cross-couplings involving two electrophiles.