Base hydrolysis redox mechanism

As stated previously only cobalt(III) and ruthenium(III) complexes are very sensitive to base hydrolysis. As these two metal centres have stable metal(II) oxidation states the possibility exists that a redox mechanism for base hydrolysis could occur. Gillard [26 ] has considered this possibility for cobalt(IIl) complexes in some detail and has... 

Cliroinium(ni) Complexes.—In an attempt to distinguish between the four possible mechanisms postulated for base hydrolysis [ Nlcb, aSnHp, /a (or A), and redox], choice of an anionic complex ion such as that found in Reinecke s salt, [NH4]+-rram-[Cr(NH3)a(NCS)4l , was made. Ion-pairing and redox reactions are not likely in this case, but the reaction is complicated by the parallel loss of NH3 and NCS ion. In strongly alkaline solution, / obs = A i +Atoh [OH ], where /ci represents the sum of two rate constants, one for the loss of NH3 and one for the loss of... 

To further examine the catalytic potential of DNA, Carmi et al. [22] employed the in vitro selection protocol described above to generate deoxyribozymes that facilitate self-cleavage by a redox-dependent mechanism. The design of this selection was based on the fact that DNA is more sensitive to cleavage via depuri-nation followed by j6-elimination or via oxidative mechanisms than by hydrolysis. Therefore, single-stranded DNA (ssDNA) bound to streptavidin by its biotin-tag was incubated with CuCl2 and ascorbate. The pool isolated after seven rounds of selection consisted of... 

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