Photochemical reactions of Fe(CO)5 with monometal alkynyls and free alkynes: Synthesis and characterization of [(η5-C 5Me5)Fe2Mo(CO)7{μ3- η1:η-4:η2C(H)C(Ph)C(Ph)C}] and diferrocenylquinones

Article abstract of DOI:10.1021/om049739y

Photolysis of a benzene solution containing Fe(CO)₅ and [(η⁵-C₅R₅)Mo(CO)₃(C≡CPh)] yielded mixed-metal clusters [(η⁵-C₅R ₅)Fe₂Mo(CO)₈(μ₃- η¹:η²:η²-CCPh)] (R = H, 1; Me, 2) and [(η⁵-C₅H₅)Fe₃Mo(CO) ₁₁(μ₄-η¹:η¹: η²:η¹-CCPh)] (3). When a mixture of [(η⁵-C₅Me₅)Mo(CO)₃(C≡CPh)] , Fe(CO)₅, and phenylacetylene was photolyzed, coupling of the acetylide and acetylene was observed and the mixed-metal cluster [(η⁵-C₅Me₅)Fe₂Mo(CO) ₇(μ₃-η¹:η⁴: η²-C(H)C(Ph)C(Ph)C)] (4) was obtained. Interestingly, use of a bulky substituent on the free acetylene in the reaction mixture did not produce analogues of 4. Reaction of Fe(CO)₅ with ferrocenylacetylene produced three different compounds, tetracarbonyl(2-ferrocenylmaleoyl)iron (5), 2,5-diferrocenylquinone (6), and 2,6-diferrocenylquinone (7). All new compounds were characterized by IR and ¹H and ¹³C NMR spectroscopy. Structures of 2-7 were established crystallographically.