Higher Nuclearity Fe,Ru Mixed-Metal Dicarbide Cluster Compounds Derived from Ethynediyldiiron Complex (η5-C5Me5)(CO)2Fe−C⋮C−Fe(η5-C5Me5)(CO)2

Abstract

Reaction of the ethynyliron complexes FP−C⋮C−H [FP = Fp (1), Fp* (1*); Fp = (η5-C5H5)Fe(CO)2; Fp* = (η5-C5Me5)Fe(CO)2] with Ru3(CO)12 in refluxing benzene affords triruthenium μ-η1(Ru1):η2(Ru2):η2(Ru3)-acetylide cluster type compounds Ru3(CO)9[μ3-η1:η2:η2-C⋮C−FP] [FP = Fp (3), Fp* (3*)] in a manner similar to the reaction of 1-alkynes. In contrast to the clean reaction of 1 and 1*, reaction of the ethynediyldiiron complex, Fp*−C⋮C−Fp* (2*), gives a complicated mixture of products, from which Cp*2Fe2Ru2(μ4-C2)(CO)10 (5*) and Cp*2Fe2Ru6(μ6-C2)(CO)17 (6*) are isolated and characterized as permetalated ethene and permetalated ethane, respectively, by X-ray crystallography. It is revealed that the permetalated hydrocarbon structures in 5* and 6* are constructed via formal addition of a dimetallic species to the C−C triple bond in 2*. The octanuclear complexes 6* and 6 (Cp derivative) are also prepared by thermal dimerization of the tetranuclear FeRu3(μ-C2) core in 3* and 3. Higher nuclearity cluster compounds including the heptanuclear dicarbide cluster compound CpFeRu6(μ5-C2)(μ5-C2H)(CO)16 (12) and the heptanuclear bis(dicarbide) cluster compound Cp2Fe2Ru5(μ5-C2)2(CO)17 (15) are obtained not only by thermolysis but also by one-electron oxidation of the deprotonated anionic form of 3 (13).