Pentacarbonyl-7H-indenediiron, [Fe₂(CO)₅(η³,η⁵-C₉H₈)] (1), reacts with aryllithium, ArLi (Ar = C₆H₅, p-C₆H₅C₆H₄), followed by alkylation with Et₃OBF₄ to give novel 7H-indene-coordinated diiron bridging alkoxycarbene complexes [Fe₂{µ-C(OC₂H₅)Ar}(CO)₄(η⁴,η⁴-C₉H₈)] (2, Ar = C₆H₅; 3, Ar = p-C₆H₅C₆H₄). Complexes 2 and 3 react with HBF₄·Et₂O at low temperature to yield cationic bridging carbyne complexes [Fe₂(µ-CAr)(CO)₄(η⁴,η⁴-C₉H₈)]BF₄ (4, Ar = C₆H₅; 5, Ar = p-C₆H₅C₆H₄). Cationic 4 and 5 react with NaBH₄ in THF at low temperature to afford diiron bridging arylcarbene complexes [Fe₂{µ-C(H)Ar}(CO)₄(η⁴,η⁴-C₉H₈)] (6, Ar = C₆H₅; 7, Ar = p-C₆H₅C₆H₄). The similar reactions of 4 and 5 with NaSC₆H₄CH₃-p produce the bridging arylthiocarbene complexes [Fe₂{µ-C(Ar)SC₆H₄CH₃-p}(CO)₄(η⁴,η⁴-C₉H₈)] (8, Ar = C₆H₅; 9, Ar = p-C₆H₅C₆H₄). Cationic 4 and 5 can also react with anionic carbonylmetal compounds Na[M(CO)₅(CN)] (M = Cr, Mo, W) to give the diiron bridging aryl(pentacarbonylcyanometal)carbene complexes [Fe₂{µ-C(Ar)NCM(CO)₅}(CO)₄(η⁴,η⁴-C₉H₈)] (10, Ar = C₆H₅, M = Cr; 11, Ar = p-C₆H₅C₆H₄, M = Cr; 12, Ar = C₆H₅, M = Mo; 13, Ar = p-C₆H₅C₆H₄, M = Mo; 14, Ar = C₆H₅, M = W; 15, Ar = p-C₆H₅C₆H₄, M = W). Interestingly, in CH₂Cl₂ solution at room temperature complexes 10–15 were transformed into the isomerized 7H-indene-coordinated monoiron complexes [Fe(CO)₂(η⁵-C₉H₈)C(Ar)NCM(CO)₅] (16, Ar = C₆H₅, M = Cr; 17, Ar = p-C₆H₅C₆H₄, M = Cr; 18, Ar = C₆H₅, M = Mo; 19, Ar = p-C₆H₅C₆H₄, M = Mo; 20, Ar = C₆H₅, M = W; 21, Ar = p-C₆H₅C₆H₄, M = W), while complex 3 was converted into a novel ring addition product [Fe₂{C(OC₂H₅)C₆H₄C₆H₅-p-(η²,η⁵-C₉H₈)}(CO)₅] (22) under the same conditions. The structures of complexes 2, 6, 8, 14, 18 and 22 have been established by X-ray diffraction studies.