The Bridging Ligand in Inner-Sphere Redox Reactions

6 The Bridging Ligand in Inner-Sphere Redox Reactions 

The early work of Taube and his co-workers opened several interesting avenues of approach, most of which have been fully exploited. 21,22, 8.B4o Qj g pj- j g obvious is to examine the 

Taube s original discovery/ Attendant changes of redox rates by many orders of magnitude have been observed. Much data have been obtained on reactions of the type 

Examination of the data for (5.49) and (5.50) in Tables 5.7 and 5.8 shows that there is some general order of reactivity for the various ligands L. Containing an unshared electron pair after coordination appears a minimum requirement for a ligand to be potential bridging group, for it has to function as a Lewis base towards two metal cations. Thus CofNHj) and Co(NH3)jpy + oxidize Cr by an outer-sphere mechanism, giving Cr as the product, at a much slower rate than for the inner-sphere reactions. 

Co(NH3)5H20, a term in the rate law containing an dependency for their reaction 

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