Reduction of transition metal complexes by organic radicals

REDUCTION OF TRANSITION METAL COMPLEXES BY ORGANIC RADICALS 

Reductions of transition metal complexes by organic radicals are very frequent. Of special importance is the 1-hydroxy-1-methylethyl radical, C(CH3)20H. This radical is presumably derived from isopropyl alcohol in which a hydrogen atom is removed from the carbon bearing the OH group. These free radicals were used by many researchers, e.g., at the Ames Laboratory and Department of Chemistry, Iowa State University, Ames, Iowa, and at the Rugjer Bo kovic Institute, Zagreb, Croatia.  

The first papers of this type were published in 1982. Two review articles by J. H. Espenson are very informative.  

The 1-hydroxy-1-methylethyl radical acts as a reducing agent (E° -1.2 V), e.g.. 

The mentioned authors prepared the C(CH3)20H radical from the [(H20)5Cr C(CH3)20H] complex, obtained in the reaction of [Cr (H20)g] + H2O2, in an acidic aqueous solution containing 2-propanol  

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