Higher Oligonuclear Metallocycles

Reaction of cobalt(III) acetate and ammonium hexafluorophosphate in methanol over one week at room temperature yielded a mixture of products that included green crystals of [NH,][Co (MeC02) (OMe),J[PF,]. The cavity in this product 

Other cyclic structures related to that of [COg(MeC02)g(OMe),g] have been reported and [V,2032] 5 [CrgFgCMe CCO ),],  

Although the presence of mixed bridging ligands may favour the formation of high nuclearity assemblies, it remains difficult to pinpoint the factors that give rise to these unusual cyclic products. In accordance with the previous discussion, it seems likely that these multi-component species may exist in solution in equilibrium with related oligomeric species their isolation will thus be influenced by both the position of the equilibrium as well as by the relative solubilities of the respective species in the chosen reaction solvent. 

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