Directed Cobalt-Catalyzed -Markovnikov Hydroalkylation of Unactivated Alkenes Enabled by "Co-H" Catalysis.

The earth-abundant cobalt-catalyzed -Markovnikov hydroalkylation of unactivated alkenes with oxime esters was achieved by introducing an 8-aminoquinoline directing group on the alkenes. The catalytic system, consisting of commercially available Co(acac) and PhMeSiH, enables the construction of unfunctionalized C(sp)-C(sp) bonds and features exclusive -Markovnikov selectivity, good functional group tolerance, and the avoidance of an extra ligand, oxidant, or base. Mechanistic insight into this new catalytic system indicates the involvement of both alkyl radical and cobalt hydride intermediates.