Pentacarbonyl rhenate

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]. 

Analogously, the reaction of rhenate pentacarbonyl anion [Re(CO)5] as its sodium salt, with cyclopropenylium cations [C3Ph3]X (X = BF4, PF6) in THF, at -80 °C, afforded the octahedral n-coordinated pentacarbonyl ( /-l,2,3-triphenylcyclopropenyl)rhenium complex in 60-73% yield (equation 195)26 269. The l3C NMR (acetone-, .) spectrum dis-... 

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