Cyclidene complexes unbridged

Electrochemical data for one unbridged and four vaulted cyclidene complexes of iron(II) appear in Table 2. The most obvious feature is the dependence of redox potential on the axial ligand. For mixed chloride/bromide derivatives, the potential is much more negative than that for complexes having neutral acetonitrile as the axial ligand. The potentials are generally consistent with values reported for lacunar iron(II) cyclidene... 

Table 2. Electrochemical data for the first oxidation reaction of vaulted and unbridged iron(II) cyclidene complexes. ... 

Figure 13. Structure of an unbridged [16]cyclidene complex showing natural cleft in the saddle shape of the molecule a) top view b) side view c) front view d) structure of a diprotonated [16]cyclidene ligand.

The totally synthetic superstmctured cobalt(II) cyclidene complexes (Figure 61) CoA (vaulted), CoB (unbridged) and CoC (lacunar), function as both oxidase and oxygenase models in oxygenation of substituted phenols . 

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