Subtleties of cobalt oxidative addition

Organometallics Chemical catalysis relies to a great extent on heavy precious transition metals that hop between oxidation states two electrons at a time. Recent efforts have focused on making greater use of the lighter, more abundant metals like iron, cobalt, and nickel. However, their tendency toward one-electron chemistry complicates the conventional mechanistic paradigms. Sandford et al. used a systematic combination of cyclic voltammetry and Hammett correlations of substituent effects to analyze the oxidative addition of a cobalt(I) complex to benzyl bromides. The results pointed to a two-step process involving a cobalt(II)-bromine intermediate and showcased the promising utility of the approach. J. Am. Chem. Soc. 141 , 18877 (2019).