Synthesis of heterometallic cluster compounds from Fe3(μ3-Te)2(CO)9 and comparisons with analogous sulfide clusters

Fe₃Te₂(CO)₉ is shown to be a useful precursor to a variety of heterometallic carbonyl clusters in reactions which appear to proceed via the intermediacy of Fe₂(Te₂)(CO)₆. Fe₃Te₂(CO)₉ decomposed in polar solvents to give Fe₂(Te₂)(CO)₆ which could be dimerized to Fe₄Te₄(CO)₁₂. Fe₃Te₂(CO)₉ reacted with C₅H₅Co(CO)₂ and Pt(C₂H₄)(PPh₃)₂ to give good yields of (C₅H₅CO)Fe₂Te₂(CO)₇ and Fe₂PtTe₂(CO)₆(PPh₃)₂, respectively. (C₅H₅Co)Fe₂Te₂(CO)₇ underwent reversible decarbonylation to give a mixture of two isomers of (C₅H₅Co)Fe₂Te₂(CO)₆ as established by ¹²⁵Te NMR spectroscopy. Upon reaction with Co₂(CO)₈, Fe₃Te₂(CO)₉ gave Co₂FeTe(CO)₉ or Co₄Te₂(CO)₁₁ depending on the reaction conditions. Co₄Te₂(CO)₁₁, like Fe₃Te₂(CO)₁₀ and (C₅H₅Co)Fe₂Te₂(CO)₇, can be reversibly decarbonylated. The assembly of Co₂FeTe(CO)₉ may be mechanistically related to the conversion of Fe₂(S₂)(CO)₆ to FeCo₂S(CO)₉ which was found to proceed via Co₂Fe₂S₂(CO)₁₁. Alternatively, Co₂Fe₂S₂(CO)₁₁ reacted photochemically with [C₅H₅Mo(CO)₃]₂ to give the known, chiral cluster (C₅H₅Mo)CoFeS(CO)₈. While Fe₂(Te₂)(CO)₆ thermally dimerized to Fe₄Te₄(CO)₁₂, Fe₂(S₂)(CO)₆ gave the analogous dimer only upon photolysis. In contrast to the stability of (C₅H₅CO)Fe₂Te₂(CO)₇, the reaction of C₅H₅Co(CO)₂ with Fe₂(S₂)(CO)₆ gave only (C₅H₅CO)Fe₂S₂(CO)₆ which is proposed to be structurally related to Fe₃S₂(CO)₉ and not (C₅H₅Co)₃S₂ or Fe₂PtS₂(CO)₆(PPh₃)₂.     

57Fe Mössbauer spectroscopic study of some clusters related to Fe3(CO)12

The ⁵⁷Fe Mössbauer spectra of Fe₃(CO)₁₂-related clusters [Fe₃(CO)₁₁]²⁻, [Fe₂Ru(CO)₁₂], [FeRu₂(CO)₁₂], [Fe₃(CO)₁₁PPh₃], [Fe₃(CO)₁₁PPh₂Me], [Fe₃(CO)₁₁PPhMe₂], [Fe₃(CO)₉(PPh₂Me)₃], [Fe₂Ru(CO)₁₁P(OMe)₃], [FeRu₂(CO)₁₁PPh₃] and [FeRu₂(CO)₁₀(PPh₃)₂] have been recorded at 78 K. The data are compared with published data for other M₃ clusters.Generally, the isomer shifts (δ) fall within a narrow range, for example with compounds containing Fe or Fe and Ru and four or five CO ligands per metal, all δ values lie between 0.29 and 0.36 mm s⁻¹ even though the ligands may be terminal, doubly bridging or triply bridging. Values of quadrupole splitting (Δ) are much more susceptible to changes in the Fe environment, for example the Fe(CO)₄ sites have Δ values from about zero {Fe(CO)₄^t in [Fe₃(CO)₁₂)]} to 1.52 {Fe(CO)₃^tCO^tbr in [Fe₃(CO)₁₁]²⁻}. The quadrupole splitting of the Fe site in [FeRu₂(CO)₁₂] (0.77 mm s⁻¹) clearly indicates that the structure of this cluster is not exactly similar to that of [Ru₃(CO)₁₂]. Substitution of CO by phosphine in general leads to small changes in Δ and Δ if the geometry of the Fe site is unaltered. However, Δ especially can be affected if phosphine substitution cause changes in geometry or if there is multiple substitution.     

Reactions of iron carbonyl complexes with dimethylthiocarbamoyl chloride

The reactions of dimethylthiocarbamoyl chloride with a number of neutral and ionic iron carbonyl complexes in tetrahydrofuran are described. A variety of unusual products were obtained, viz. Fe(CO)₂(S₂CNMe₂)₂ from Fe(CO)₅; Fe(CO)₂(S₂CNMe₂)(CSNMe₂) from Fe₂)CO)₉, Fe₃(CO)₁₂, and Fe(CO)₄^2?; [Fe-(CO)₂(S₂CNMe₂)(CNMe₂)(CNMe₂)₂S]⁺ from Fe(CO)₄^2?, and Fe₄(CO)₁₂S(CSNMe₂)-(CNMe₂) from Fe₂(CO)₈^2?, as well as Fe₂(CO)₆(CSSEt)₂ from Fe₂(CO)₉ and ClCSSEt. The structures and behavior and some reactions of these complexes are described.     

Reduction—complexation des sulfures de phosphines par les fer-carbonyles

1-Phenyl-3,4-dimethylphosphole (L) yields the classic σ complex LFe(CO)₄ with Fe₂(CO)₉ and the unsual σ,π complex LFe₂(CO)₇ with Fe₃(CO)₁₂, whereas 1-t-butyl-3,4-dimethylphosphole (L′) with Fe₃(CO)₁₂ yields L′Fe₂(CO)₆ which belongs to a type already described in the literature. With Fe₂(CO)₉ at 85°C, the phosphole sulfide LS yields the two σ and σ,π complexes directly by reduction—complexation. This Fe₂(CO)₉ reduction—complexation process works only with phosphole and phospholene sulfides. However, with Fe(CO)₅ in great excess at 150°C, a general phosphine sulfide reduction—complexation procedure takes place. A study of the displacement of 1-phenyl-3,4-dimethyl-3-phospholene (L″) from its σ complex L″Fe(CO)₄ by trimethylphosphite has shown that L″ has a greater complexing ability toward iron than the phosphite, contrary to what could be expected from the work of Tolman on nickel complexes.     

Ligand exchange processes in some iron-sulphur-carbonyl and -nitrosyl complexes

The complex [Fe₂(SMe)₂(CO)₆] undergoes stepwise exchange with Et₂S₂ to yield successively [Fe₂(SMe)(SEt)(CO)₆] and [Fe₂(SEt)₂(CO)₆]. Carbonyl complexes [Fe₂(SR)₂(CO)₆] are efficiently converted to the nitrosyls [Fe₂(SR)₂(NO)₄] by the action either of NO gas or of methanolic sodium nitrite: the analogous species [Fe₂S₂(CO)₆], [Fe₂S₂(CO)₆]^2?, and [Fe₃S₂(CO)₉] all, with methanolic nitrite, yield [Fe₄S₃(NO)₇]^?. This anion, [Fe₄S₃(NO)₇]^?, reacts with sulphur to give the cubane-like [Fe₄S₄(NO)₄]: the synthesis of its selenium analogue, [Fe₄Se₃(NO)₇]^? is described. The complexes [Fe₂(SR)₂(NO)₄] (R = Me, Et, Prⁿ, Prⁱ, Bu^t, PhCH₂) all consist of two isomers in solution, presumed to have structures of C_2h and C_2v, symmetry: activation parameters for the C_2h?C_2v reaction are reported.     

Esr study of the reaction of iron carbonyls with sodium alkylthiolates

Conclusions The reaction of iron carbonyls with sodium alkylthiolates proceeds by redox-disproportionation through one-electron transfer to form the Fe₂(CO)₈ , Fe₃(CO)₁₁ Fe₄(CO)₁₃ , and Fe₃(CO)₁₂ radical-anions. Fe₂(CO)₆(SR)₂ and Fe₃(CO)₉(SR)₂ radical-anions are paramagnetic analogs of the reaction products, Fe₂(CO)₆(SR)₂ and Fe₃(CO)₉(SR)₂, and were detected by ESR spectroscopy.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1652–1654, July, 1987.     

Syntheses,crystal structures,and electrochemical studies of diiron complexes from the reactions of [Et3NH][(μ-RS) Fe2(CO)6(μ-CO)] with isothiocyanates

Reactions of [Et₃NH][(μ-MeO₂CCH₂S)Fe₂(CO)₆(μ-CO)] in situ generated from the mixture of MeO₂CCH₂SH, Et₃N, and Fe₃(CO)₁₂ with 2-C₅H₄NNCS, 3-C₅H₄NNCS, and EtNCS in THF, form 1, (μ-MeO₂CCH₂S)Fe₂(CO)₅(μ-k²N,S:k²C-2-C₅H₄NNHCS), 2, (μ-MeO₂CCH₂S)Fe₂(CO)₆(μ-k²C,S-3-C₅H₄NNHCS), and 3, (μ-MeO₂CCH₂S)Fe₂(CO)₆(μ-k²C,S-EtNHCS). Reaction of [Et₃NH][(μ-PhS)Fe₂(CO)₆(μ-CO)] in situ formed from the mixture of PhSH, Et₃N, and Fe₃(CO)₁₂ with EtNCS affords 4, (μ-PhS)Fe₂(CO)₆(μ-k²C,S-EtNHCS). Reaction of [Et₃NH][(μ-EtS)Fe₂(CO)₆(μ-CO)] in situ produced from the mixture of EtSH, Et₃N, and Fe₃(CO)₁₂ with EtNCS offers 5, (μ-EtS)Fe₂(CO)₆(μ-k²C,S-EtNHCS). All new complexes have been fully characterized by EA, IR, ¹H NMR, and ¹³C NMR and structurally determined by X-ray crystallography. Electrochemical studies on 2 and 5 confirm that 2 shows high H₂-producing activity.     

Syntheses of Novel Fe/S Clusters with μ‐Aminocarbyne Ligands

The reaction of Fe₃(CO)₁₂ with (C₃H₅)₂NCS₂K in THF at room temperature afforded a red‐brown solution. Treatment of the thus‐obtained solution with MeI and PhCH₂Br afforded clusters 1 , (μ‐MeS)Fe₂(CO)₆(μ₄‐S)Fe₂(CO)₆(μ‐CN(C₃H₅)₂), and 2 , (μ‐PhCH₂CO)Fe₂(CO)₆(μ₄‐S)Fe₂(CO)₆(μ‐CN(C₃H₅)₂). Their structures were unambiguously determined by X‐ray crystallography. Therefore, this methodology provides a novel route for the syntheses of spiro‐S Fe/S clusters with aminocarbyne ligands.     

The formation of iron carbonyl radical anions in the reactions of iron carbonyls with trimethylamine N-oxide

The interaction of iron carbonyls, Fe(CO)₅, Fe₂(CO)₉ and Fe₃(CO)₁₂ with Me₃NO occurs according to a one-electron redox-disproportionation scheme giving rise to iron carbonyl radical anions: Fe₂(CO)₈^·− (1), Fe₃(CO)₁₂^·− (2), Fe₃(CO)₁₁^·− (3) and Fe₄(CO)₁₃^·− (4). The role of Me₃NO, inducing CO-substitution, consists of the generation of reactive 17-electron species with a labile coordination sphere in which the substitution for other ligands occurs, resulting from fast ligand and electron exchange in the confines of the ETC-reaction.     

Carbonyliron complexes with an azomethylene moiety: V. Preparation of Fe3(PhCH2N)(CO)10 and HFe3(PhCHN)(CO)9 from benzalazine and Fe3(CO)12. X-ray crystal structure of μ-(o-C6H4CH2NNCHPh)Fe2(CO)6

The precipitate formed by the reaction of benzalazine with Fe₃(CO)₁₂ yields the triangular clusters Fe₃(PhCH₂N)(CO)₁₀ and HFe₃(PhCHN)(CO)₉ when decomposed by concentrated hydrochloric and phosphorous acids, respectively. The structure of μ-(o-C₆H₄CH₂NNCHPh)Fe₂(CO)₆, a product obtained from the benzalazine and Fe₃(CO)₁₂ reaction, is discussed.     

Unsaturation in binuclear iron trifluorophosphine carbonyl derivatives: comparison with binary iron carbonyls

Bridging PF₃ groups are obviously very unfavorable as indicated by their absence in Fe₂(CO) _n (PF₃)₂ (n?=?7,?6,?5,?4) complexes optimized by density functional theory even though many such structures have one or more bridging CO groups. Except for some Fe₂(CO)₇(PF₃)₂ structures, the two terminal PF₃ groups are bonded to different irons. Structures of the saturated Fe₂(CO)₇(PF₃)₂ having one, two, and three bridging or semibridging CO groups have similar energies suggesting a fluxional system. The lowest energy structures for the unsaturated Fe₂(CO) _n (PF₃)₂ (n?=?6,?5,?4) derivatives are triplet spin-state structures. However, higher energy singlet Fe₂(CO) _n (PF₃)₂ (n?=?6,?5,?4) structures are found having formal iron–iron multiple bonds and various combinations of bridging and terminal CO groups leading to the favored 18-electron configurations for iron. Most singlet Fe₂(CO) _n (PF₃)₂ (n?=?6,?5,?4) structures are analogous to those of the previous studied Fe₂(CO) _{n +2} structures.     

Seleniumselenium bond reactions of μ-(diselenium)bis(tricarbonyliron), an inorganic mimic of organic diselenides

μ-(Diselenium)bis(tricarbonyliron), (μ-Se₂)Fe₂(CO)₆, has been found to have reactivity typical of organic diselenides, RSeSeR. Reaction with two molar equivalents of LiBEt₃H converts (μ-Se₂)Fe₂(CO)₆ to the dianion, (μ-LiSe)₂Fe₂(CO)₆. Organolithium reagents, RLi, cleave its SeSe bond, giving (μ-LiSe)(μ-RSe)Fe₂(CO)₆. Low valent transition metal species, e.g., (Ph₃P)₂Pt, insert into the SeSe bond. (μ-Se₂)Fe₂(CO)₆ is fragmented by the action of dicobalt octacarbonyl, giving (μ₃-Se)FeCo₂(CO)₉.     

Reaction of styrene with sulfur and triiron dodecacarbonyl and the molecular structure of the complex Fe2(CO)6(SCH2S)

Reaction of excess styrene with Fe₃(CO)₁₂ and sulfur (60°C, 15 h, Ar, S/Fe₃(CO)₁₂ 0.6 g-atom/mole) gave Fe₂(CO)₆S₂, Fe₃(CO)₉S₂, Fe₂(CO)₆(S₂CO), Fe₂(CO)₆S₂(PhCHCH₂), PhCHCH₂S₄, and a novel binuclear complex Fe₂(CO)₆(S₂CH₂S), whose structure was analyzed by x-ray crystallography. The crystals are monoclinic, a=7.764(3), b=13.205(4), c=6.628(6) Å, =98.97(3)°. V=671.2(7) ų, Z=2, space group P2₁/m. The bond lengths are Fe-Fe 2.520(2), Fe-S 2.236(2), S-S 2.078(4), C-S 1.825(12), Fe-CO 1.784(8), and CO 1.148(9) Å.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 930–934, April, 1991.     

Heterometallic iron carbonyl chalcogenide clusters containing ruthenium,rhenium, manganese,and molybdenum

The reactions of Fe₂Se₂(CO)₆ (1b) with Ru(CO)₄(C₂H₄), Mn₂(CO)₁₀, or Np"Re(CO)₂THF gave the known cluster Fe₂RuSe₂(CO)₉ (4b) and new clusters (CO)₆Fe₂Se₂Mn₂(CO)₈ (5) and Cp"Re(CO)₂Se₂Fe₂(CO)₆ (6). By successive reactions of Mo(CO)₅THF with 1b and Fe₂Te₂(CO)₆, the new heterometallic heterochalcogenide cluster Fe₂(CO)₆(₃-Se)₂Mo(CO)₂(₃-Te)₂Fe₂(CO)₆ (8) was synthesized. The structures of 4b, 5, and 6 were determined by X-ray diffraction analysis.     

Mössbauer study of some Fe-containing M6 and M5 clusters

Isomer shift (δ) and quadrupole splitting (Δ) parameters have been assigned to the iron sites in [FeRh₅(CO)₁₆]⁻, trans- and cis-[Fe₂Rh₄(CO)₁₆]²⁻, [Fe₃-Rh₃(CO)₁₇]³⁻, [FeRh₄(CO)₁₅]²⁻, [Fe₃Pt₃(CO)₁₅]²⁻ and [Fe₄M(CO)₁₆]²⁻ (M = Pd or Pt) from ⁵⁷Fe Mössbauer spectra recorded at 78 K. The data for the closo compounds [FeRh₅(CO)₁₆]⁻ and [Fe₂Rh₄(CO)₁₆]²⁻ are compared with those for [Fe₆(CO)₁₆C]²⁻. In [Fe₃Rh₃(CO)₁₇]³⁻, the three major Fe sites were identified. For both [Fe₄M(CO)₁₆]²⁻ compounds two isomers were shown to be present in the solid state.     

The Reaction of μ-dithiobis(tricarbonyliron) with dimanganese decacarbonyl: a novel product and an interesting structural problem

The photo-induced reaction of (μ-S₂)Fe₂(CO)₆ and Mn₂(CO)₁₀ in tetrahydrofuran solution gave a complex of composition S₂Fe₂Mn₂(CO)₁₄. A combination of X-ray crystallography, Mössbauer spectroscopy, mass spectroscopy and elemental analysis established this composition and the structure as Fe₂Mn(CO)₉(μ₃-S)(μ₄-S)Mn(CO)₅, the Fe₂Mn system of which contains one FeFe and one FeMn bond.     

Übergangsmetall-heteroallen-komplexe XVII .Reaktionen des aza-allyl-komplexes (ketenimin)Fe2(CO)6 mit phosphanen

The aza-allyl complex (ketene imine)Fe₂(CO)₆ (3a) reacts with phosphanes PR₃ to give substitution products of the type (ketene imine)Fe₂(CO)₅PR₃ (4a,b). In addition, the phosphane PMe₃ yields a ferrole complex (5). Phosphites react with complex 3a to form mono- and di-substitution products (ketene imine)- Fe₂(CO)₅P(OR)₃ (4c,d) and (ketene imine)Fe₂(CO)₄(P(OR)₃)₂ (6). Diphosphanes yield substituted complexes of type (ketene imine)Fe₂(CO)₄(μ-Ph₂P ^⌢ PPh₂) (7). The structures of (ketene imine)Fe₂(CO)₅PMe₃ (4a), the ferrole complex 5, and (ketene imine)Fe₂(CO)₄(ν-Ph₂PCH₂CH₂PPh₂) (7b) were determined by X-ray analysis.     

Unsaturation in binuclear iron carbonyl complexes of the split (3 + 2) five-electron donor hydrocarbon ligand bicyclo[3.2.1]octa-2,6-dien-4-yl: Role of agostic hydrogen atoms

The experimentally known split (3 + 2) five-electron donor bicyclo[3.2.1]octa-2,6-dien-4-yl (bcod) ligand provides a flexible alternative to the rigid planar cyclopentadienyl (Cp) ligand. In this connection, the structures and energetics of the binuclear iron carbonyl complexes (bcod)₂Fe₂(CO)_n (n = 4, 3, 2, 1) have been investigated by density functional theory for comparison with the corresponding Cp₂Fe₂(CO)_n derivatives. The cis and trans doubly CO-bridged (bcod)₂Fe₂(μ-CO)₂(CO)₂ structures are the lowest energy tetracarbonyl structures, similar to the Cp₂Fe₂(CO)₄ system. However, an unbridged (bcod)₂Fe₂(CO)₄ isomer lies only ~1 kcal/mol in energy above the doubly bridged isomers. The flexibility of the bcod ligand leads to low-energy singlet and triplet spin state structures with agostic hydrogen atoms for the unsaturated (bcod)₂Fe₂(CO)_n (n = 3, 2, 1) systems. Analogous structures are not found in the corresponding Cp₂Fe₂(CO)_n systems with the rigid Cp ligand. Such structures, effectively involving donation of an electron pair from an olefinic C-H bond to an iron atom through three-center two-electron C-H-Fe bonding, are energetically competitive with isomeric structures with metal-metal multiple bonds.     

The synthesis of some mixed metal cluster complexes of osmium with cobalt and iron

The reactions of cis-dihydridotetracarbonylosmium, H₂Os(CO)₄ with both Fe₂(CO)₉, and Co₂(CO)₈ have been studied at room temperature. With Fe₂(CO)₉ the major product is Fe₂Os(CO)₁₂ and H₂FeOs₃(CO)₁₃ was obtained as a minor product. With Co₂(CO)₈, Co₂Os(CO)₁₁ and H₂Co₂Os₂(CO)₁₂ are obtained, along with an unstable compound which was identified mass spectrometrically as HOsCo(CO)₈. Os(CO)₅ reacts under UV irradiation with Co₂(CO)₈ to give Co₂Os(CO)₁₁. The main product of the reaction of H₂Os₂(CO)₈ with Fe₂(CO)₉ is FeOs₂(CO)₁₂.