Oxo-iron aggregates

The structural chemistry of oxo-iron aggregates is dominated by the presence of and /<3-oxo groups which, in conjunction with other ligands, confer stability to the polynuclear core. For structurally characterized synthetic complexes, the degree of aggregation varies to date from three to eleven, but neither a decanuclear nor any odd numbered intermediate size is known. 

The two dinuclear units are linked by /13-oxo and /i-carboxylato groups. The third position in the "coordination sphere" of the /13-oxo groups is occupied by an unusual 5 coordinate, trigonal bipyramidal iron atom. This is the only case known so far in oxo-iron aggregates. The /13-oxo bridge is of type B since the surrounding metal atoms form an isosceles triangle. 

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