Synthesis and characterization of ferrocenylchalcogenopropargyl complexes [Fe(η⁵-C₅H₄E^ICH₂C≡CH)₂] (E^I = Se, S) and their reactions to form unusual ferrocenyl-containing metal clusters with eclipsed Cp rings and new five-membered FeE^ICHC=CH₂ ring ligand system

Abstract

The new bis(chalcogenopropargyl)ferrocene complexes [Fe(η⁵-C₅H₄E^ICH₂C≡CH)₂] (E^I = Se, 1; E^I = S, 2) have been prepared by treatment of the dilithiated [Fe(η⁵-C₅H₄Li)₂] with Se or S powder, followed by reaction with propargyl bromide. Reaction of 1 and 2 with [Fe₂M(μ₃-E)₂(CO)₉] (E = S, Se and M = Fe, Ru) forms new clusters which feature an unusual five-membered FeE^ICHC=CH₂ ring with a π bond between the olefinic unit and the Fe atom, and the Cp rings adopt an eclipsed arrangement. The structures of 1 and [Fe(η⁵-C₅H₄E^ICH₂C≡CH)(η⁵-C₅H₄{Fe₂M(CO)₈(μ-E)(μ₃-E)(E^ICHCCH₂)})] (M = Fe, E = Se, E^I = Se, 3; M = Fe, E = S, E^I = Se, 4; M = Ru, E = S, E^I = Se, 7) have been determined crystallographically.