Cobalt III Bonds

Carbon-Cobalt(iii) Bonds.—These bonds are readily formed in reactions of aliphatic free radicals with Co complexes. Reaction of CHgOH, MeCHOH, HOCHCH2OH, or CHaCHO with the macrocyclic complex [Co K2)J produces the unstable intermediate [Co (2)—RH] containing a cr-carbon-cobalt bond  

Alkylnitroso Complexes.—Reduced nitrosyl complexes such as [Fe(CN)6(NO)] and [Ru(NH3)5(NO)] + react with alkyl free radicals to yield the corresponding A-bound alkylnitroso-complexes 

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The coordinatively unsaturated cobalt(II) complex has a significant tendency to react with the growing carbon radical and form the carbon-cobalt(III) bond, which enables several radical reactions with cobalt complexes, but inhibits the atom transfer radical reactions. Thus, cobalt is the representative transition metal, of which complexes can mediate the controlled OMRP via a reversible formation of the growing radical from the C-Co(III) bond. 

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