Synthesis of organocobalt complexes via cobalt II reagents

Cobalt(II) reagents in several equatorial hgand systems are also known to react with 

As exemplified by Eqn. 19, cobalt(II) complexes can efficiently trap organic radicals to form organocobalt complexes. Hence, organic radicals generated by means other than the atom-transfer step of Eqn. 18 may also be used to alkylate cobalt(II) complexes. Thus, Roche and Endicott [63] generated organic radicals by photolysis of carboxylatopentaammine-cobalt(III) complexes in acidic media (Eqn. 20) 

Reaction kinetics were first order in cobalt(II) chelate and first order in hydroperoxide and the second-order rate constants were surprisingly insensitive to the nature of the cobalt chelate equatorial ligand system over a wide variety of cobalt chelates. 

Finally, Goedken and coworkers [64] have shown that cobalt(II) complexes react with organohydrazines in the presence of molecular oxygen to produce organocobalt products, in some cases in very high yield (Eqn. 24). 

Although it has not been very thoroughly studied, this exothermic reaction occurs for cobalt(II) complexes in a number of equatorial ligand systems. Brown and coworkers [59] have attempted to use this procedure for the preparation of sub- 

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