Rhenate , with bonds

The reaction of (TPP)Fe=CCl2 with pentacarbonyl rhenate may proceed by substitution of one chloride by ReCCO) " and addition of another ReCCO) " anion to a (CCl)-bridged intermediate. The iron carbon bond [1.605(13)A] of the complex (TPP)Fe=C-Re2(CO)0 appears to be the shortest metal carbon bond so far reported [20]. 

The molecular structure of the dehydrated surface rhenate species is shown in Figure 1.5. The surface rehenate species is always isolated and possesses three terminal Re=0 bonds and one bridging Re-0 support bond. The molecular structure of the dehydrated surface rhenium oxide species is consistent with the known... 

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