Activation of a High-Valent Manganese–Oxo Complex by a Nonmetallic Lewis Acid
نویسندگان
چکیده
The reaction of a manganese(V)-oxo porphyrinoid complex with the Lewis acid B(C6F5)3 leads to reversible stabilization of the valence tautomer Mn(IV)(O)(π-radical cation). The latter complex, in combination with B(C6F5)3, reacts with ArO-H substrates via formal hydrogen-atom transfer and exhibits dramatically increased reaction rates over the Mn(V)(O) starting material.
منابع مشابه
Lewis‐Acid‐assisted Hydrogen Atom Transfer to Manganese(V)‐Oxo Corrole through Valence Tautomerization
The kinetics of formation of the valence tautomers (tpfc⋅)MnIV(O-LA)] n+ [where LA=ZnII, CaII, ScIII, YbIII, B(C6F5)3, and trifluoroacetic acid (TFA); tpfc=5,10,15-tris(pentafluorophenyl) corrole] from (tpfc)MnV(O) were followed by UV/Vis spectroscopy, giving second-order rate constants ranging over five orders of magnitude from 10-2 for Ca to 103 m -1 s-1 for Sc. Hydrogen atom transfer (HAT) ...
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