There are only 14 electrons, so this structure does not obey The Eighteen Electron Rule. As drawn the C-5 ring would be C₅H₄ and only give 1e^- (¹). This is wrong. For stability C₅H₄ need giving all 5e- (⁵). Fe bonds to all the carbons in the ring.
(Phosphorus has 5 valence electrons, s²p³, but there are 3 valence electrons used by the 3 Phenyl-groups, so there are just 2 valence electrons left for the bonding with Fe.)
 

Fe      = 8e- C5H4 = 1e- COT  = 2e- CH3   = 1e- PPh3  = 2e-              14e-

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