Inorganic Chemistry, Vol.40, No.20, 5066-5067, 2001
Indication of a hydrogen-atom abstraction reaction relevant to a mechanistic proposal for the oxygen-evolving complex of photosystem II
The hydroxide-bridged Cr(III)-Mn(II) complex [(Me(3)tacn)Cr(mu -OH)(mu -CH3CO2)(2)Mn(MeDPA)](2+) (Me(3)tacn = tri-N,N ' ,N " -methyltriazacyclononane, MeDPA = N-methyl-N-bis(2-pyridylmethylamine) is oxidized by the 2,4,6-triphenylphenoxide radical to give the oxo-bridged Cr(III)-Mn(III) complex [(Me(3)tacn)Cr(mu -O)(mu -CH3CO2)(2)Mn(MeDPA)](2+). This reaction is a potential model for H-atom abstraction steps in mechanistic proposals for water oxidation in photosynthesis. [GRAPHICS]