Oxidative addition and C-H activation chemistry with a PNP pincer-ligated cobalt complex

The bis(phosphino)pyridine (PNP) cobalt(I) methyl complex, ((PNP)-P-iPr) CoCH3 is a rich platform for the oxidative addition of non-polar reagents such as H-2, the C-H bonds of arenes and terminal alkynes. Rare e-amples of he-acoordinate cobalt(III) compounds including a trihydride, a bis(acetylide) hydride and a trimethyl comple- have been isolated and two e-amples structurally characterized. These findings demonstrate that when placed in an appropriately strong ligand field, two- electron o-idative addition chemistry is possible with first row transition metals.