121Sb and57Fe Mössbauer spectra of antimony-containing iron carbonyl complexes: [HSb{Fe(CO)4}3]2− and [Sb{Fe(CO)4}4]3−

¹²¹Sb Mössbauer spectra of the title complexes, whose isomer shifts are intermediate between the organoantimony(III) and organoantimony(V) compounds, suggest that considerable electrons are donated from hydrido ligand and Fe(CO)₄ fragments to the antimony atom.     

Synthesis and crystal structure of [NEt4]2[HFe3Rh(CO)12], the first tetranuclear FeRh hydridocarbonyl cluster

The anion [HFe₃Rh(CO)₁₂]²⁻ was obtained by reaction of [HFe(CO)₄]⁻ with Rh₂(CO)₄Cl₂ in refluxing THF. Its solid state structure consists of a tetrahedron of metal atoms with three edge-bridging and nine terminal carbonyl groups. The hydridic ligand bridges a face containing the rhodium atom. [NEt₄]₂[HFe₃Rh(CO)₁₂] crystallizes in the orthorhombic space group Pnnma, with a 19.983(5) Å, b 15.168(4) Å. c 11.915(2) Å, V 3611(2) ų, Z = 4, R = 0.043, R_w = 0.054 for 1680 unique reflections with I > 3σ(I).     

From an {Fe4S4}-cluster to {Fe2S2}- and {Fe3S}-carbonyls. Crystal structure of [Fe3S(CO)9]2−

We report the electrochemical and chemical synthesis of the first isolable iron carbonyls obtained directly from an {Fe₄S₄}-cluster and carbon monoxide: the structure of one product of chemical reduction, [Fe₃S(CO)₉]²⁻, had been determined by X-ray crystallography.     

Coupling insertion reactions of diphenylbuta-1, 4-diyne into iron-carbene bonds of [Fe2(CO)7{μ-C(Ph)C(NEt2}]. Syntheses and reactivities of the ferracyclopentadiene [Fe2(CO)6{C(Ph)C(NEt2)C(Ph)C(C2Ph)}] with [Fe2(CO)9]

The diiron ynamine complex [Fe₂(CO)₇{-C(Ph)C(NEt₂)}] (1) reacts with the diphenylbuta-1, 4-diyne, PhCC-CCPh, in refluxing hexane to yield three isomer complexes [Fe₂(CO)₆{C(Ph)C(NEt₂)C(Ph)C(C₂Ph}] (2a), [Fe₂(CO)₆{C(Ph)C(NEt₂)C(C₂Ph)C(Ph)}] (2b), and [Fe₂(CO)₆{NEt₂)C(Ph)C(C₂)C(Ph)}] (2c) All three compounds were identified by their¹H NMR spectra. Compounds2a and2c were characterized by single crystal X-ray diffraction analyses. Crystal data: for2a: space group = P2₁/n,a = 17.873(1) Å, = 18.388(6) Å,c = 9.429(3) Å = 91.99(3)°,Z = 4.3751 reflections,R = 0.044; for2c: space group = P2₁/n,a = 40.58(2) å,b = 12.101(9) Å,c = 12.551(5) Å, = 94.29(7)°,Z = 8.4723 reflection,R = 0.076. Complexes2a and2b result from a [2 + 2] cycloaddition between one of the CC triple bonds of the diyne ligand and the FeC carbene bond, whereas2c results from insertion of one of the CC group into the bridging carbene. Addition of [Fe₂(CO)₉] on2a gave two major products, the tripledecker [Fe₃(CO)₈{C(Ph)C(NEt₂)C(C₂Ph)}], (3 and a tetrairon cluster [Fe₄(CO)₁₁{C(Ph)C(NEt₂)C(Ph)C(C₂Ph)}] (4). Both compounds were characterized by single crystal diffraction analyses. Crystal data: for3: space group = P2₁/n,a = 12.039(3) Å,b = 18.046(3) å,c = 15.270(2) Å, = 90.11(2)°,Z = 4, 1430 reflections,R = 0.067; for4 space group = C2/c,a = 18.633(3) Å,b = 21.467(1)_Å,c = 20.742(2) Å, = 115.03(8)°,Z = 8.992 reflections, R = 0.076. Complex4 is based on a spiked triangular cluster with the alkynyl triple bond attached in ₃-parallel mode on the triangular grouping.     

Synthesis,chemical and biological properties of &{Pt[S(CH2)3Cl]2}6 and Pt[C6H3(oCH2CH  CH2)(p-CH3)]2

PtCl₄²⁻ with the ligand HS(CH₂)₃Cl affords a linear polymer which is converted into the hexamer title compound by heating in xylene in the presence of a small amount of dimethylsulphoxide. The hexamer undergoes Cl substitution upon reaction with NaBr or NaI. From the reaction of PtCl₂ with the Grignard reagent of o-allyl-p-methyl-chlorobenzene is obtained the monomer complex Pt[C₆H₃(CH₂CH  CH₂-o) (CH₃p)]₂. The biological properties of the complexes as inhibitors of DNA, RNA and protein synthesis has been evaluated.     

Heteronuclear (WFe) and homonuclear (FeFE) μ-alkylidene complexes of transition metals from mononuclear terminal carbene complexes. crystal structures of {WFe[μ-η1, η3-C(OCH2CH3)(CHCHCH3](CO)8} and [fe2{μ-η2,η3-C[OCH2CH3[CHC(OCH2CH3)(CH3]}(CO)6

The reactions of mononuclear carbene complexes of W and Fe of the type CO)_mMC(OR)(CH_2nCHCR′″ (M  = FE, W; m = 4 and 5; n = 0, 2, 3; R′, R″ = C, CH₃, OEt) with Fe(CO)₅ have been studied. In all cases the reaction leads to new hetero (WFe) or homo (FeFe) μ-alkylidene complexes, the position of the double bond depending strongly on n.     

Phosphine-centred resolution of (η4-diene)Fe(CO)3 complexes: (η4-tropone)Fe(CO)2L and (η4-isoprene)Fe(CO)2L [L = (+)-(neomenthyl)PPh2]

(η⁴-Tropone)Fe(CO)₃ and (η⁴-isoprene)Fe(CO)₃ form separable diastereoisomers on substitution of CO by (+)-(neomenthyl)PPh₂. In the tropone complex, diastereoisomer interconversion occurs by a 1,3-metal shift. The absolute configuration of the isoprene complex has been determined crystallographically.     

Synthesis,chemical, and electrochemical characterization of the [Ag13{μ3-Fe(CO)4}] n− (n = 3, 4, 5) cluster anions: X-Ray structural determination of [N(PPh3)2]3 [Ag12(μ12-Ag){μ3Fe(CO)4}8]1

The oxidation of the [Fe(CO)₄]^2– dianion with Ag⁺ salts occurs through a particularinner-sphere mechanism, which involves an intermediate cascade of silver clusters stabilized by Fe(CO)₄ ligands. The last detectable Ag-Fe cluster of the sequence is the [Ag₁₃{-Fe(CO)₄}₈]^3– trianion, which has been selectively obtained by using ca. 1.7 equivalents of Ag⁺ per mole of [Fe(CO)₄]^2–. The [Ag₁₃{-Fe(CO)₄}₈]^3–- trianion has been isolated in a crystalline state with several quaternary cations, and has been characterized by X-ray diffraction studies of its bis(triphenylphosphine)iminium salt. [N(PPh₃)₂]₃ [Ag₁₃{ ₃-Fe(CO)₄}₈]·2(CH₃)₂CO, monoclinic, space group P2₁ (No.4),a = 16.284(2) Å,b =18.767(5) Å,c = 25.905(4) Å, = 90.46(1)°,V = 7916(3) ų,Z = 2,R = 0.0324. The molecular structure of the anion consists of a centered cuboctahedron of silver atoms with the triangular faces capped by Fe(CO)₄ units. Chemical reduction of ( Ag₁₃{ ₃-Fe(CO)₄}₈]^3– affords the corresponding [Ag₁₃{ ₃-Fe(CO)₄)₈]^4–, which in turn gives [Ag₁₃{ ₃-Fe(CO)₄)₈]^5– and [Ag₆{ ₃-Fe(CO)₄}₄]^– upon further reduction. Electrochemical investigations confirm the reversibility of the [Ag₁₃{ ₃-Fe(CO)₄}₈]^3–/4– redox change. Furthermore, in spite of some electrode poisoning effects, evidence of the existence of the [Ag₁₃{ ₃-Fe(CO)₄}₈]^5– pentaanion was obtained. The yet structurally uncharacterized [Ag₆{ ₃-Fe(CO)₄)₄]^2– dianion is quantitatively obtained by reaction of [Fe(CO)₄]^2– with ca. 1.5 equivalents of Ag⁺ or by addition of one equivalent of Ag⁺ to solutions of the [Ag₅{Fe(CO)₄}₄]^3– trianion. All attempts to isolate its quaternary salts as crystalline materials failed owing to formation of amorphous insoluble precipitates. The above series of ₃-Fe(CO)₄ octa-capped cuboctahedral Ag₁₃ clusters can be envisioned as the Ag⁺ . Ag and Ag^– cryptates of the [Ag₁₂{}₃-Fe(CO)₄}₈]^4– cryptand. respectively.Dedicated to Prof L. F. Dahl on his 65th birthday.     

Organometalloidal derivatives of the transition metals: XI. Synthesis and crystal structures of Ph3GeSiMe3 and Ph3GeSiMe2Fe(CO)2(η5-C5H5)

Ph₃GeSiMe₃ and Ph₃GeSiMe₂Fe(CO)₂(η⁵-C₅H₅) have been synthesized and their crystal structures determined. The GeSi bond in iron (2.405(2) Å) is longer by 0.021 Å than in the simple germylsilane (2.384(1) Å). The significant shortening of the SiFe bond (2.328(1) Å) in the iron complex compared to that in the analogous Ph₃SiSiMe₂Fe(CO)₂(η⁵-C₅H₅) (2.346(1) Å) and spectroscopic data indicate an enhanced SiFe interaction.     

Synthesis and structure of osmium complexes [Ph3PR]2[OsCl6]·4DMSO

Russian Journal of General Chemistry - Reaction of sodium hexachloroosmate(IV) dihydrate with (2-oxopropyl)- and (2-carboxyethyl)-triphenylphosphonium chlorides in dimethyl sulfoxide afforded...     

Preparation and crystal structures of [μ-SbPh2]2[Mo(CO)2(η5-C5H5)]2·CHCl3 and SbPh[Fe(CO)2(η5-C5H5)]2

Antimony is reduced when [SbPh₂BrO]₂ is treated with Na[Mo(CO)₃(η⁵-C₅H₅)] to produce [μ-SbPh₂]₂[Mo(CO)₂(η⁵-C₅H₅)]₂. A structure determination shows diphenylstibido groups bridging between two Mo(CO)₂(η⁵-C₅H₅) moieties giving a central ‘butterfly’ shaped Sb₂Mo₂ ring. The cyclopentadiene rings are trans to each other and Mo–Sb and Sb–Sb separations are both short. An iron analogue could not be obtained from [SbPh₂BrO]₂ and Na[Fe(CO)₂(η⁵-C₅H₅)] but a mixture of SbPh[Fe(CO)₂(η⁵-C₅H₅)]₂ and SbPh₂[Fe(CO)₂(η⁵-C₅H₅)] was obtained using SbPh₂Cl. An X-ray structure for SbPh[Fe(CO)₂(η⁵-C₅H₅)]₂ shows an open stibinidine structure.     

The preparation of a series of ring-linked derivatives of [Fe2(η-C5H5)2(CO)2(μ-CO)2] starting from [Fe2η5,η5-C5H4CH(NMe3)CH(NMe2)C5H4}(CO)2(μ-CO)2]+ salts

The salts [Fe₂η⁵,η⁵-C₅H₄CH{NMe₃)CH(NMe₂)C₅H₄}(CO)₂(μ-CO)₂][X] (X = I or SO₃CF₃) are the synthetic precursors to a wide range of [Fe₂(η-C₅H₅)₂(CO)₂(μ-CO)₂] derivatives in which the two cyclopentadienyl ligands are joined by a two-carbon bridge.     

Penta- and hexaphospha ferrocenes as ligands: crystal and molecular structures of [Fe(η5-P3C2tBu2)2W(CO)5], [Fe(η5-P3C2tBu2)(η5-P2C3tBu3)W(CO)5] and the novel triruthenium carbonyl cluster complex [Fe(η5-P3C2tBu2)2Ru3(CO)10] containing two interlinked η5-P3C2tBu2 ring systems

The lone-pair electrons of one of the two directly bonded phosphorus atoms of the P₃C₂^tBu₂ ring in the penta- or hexaphosphaferrocene complexes [Fe(η⁵-P₃C₂^tBu₂)(η⁵-P₃C₂^tBu₃)] and [Fe(η⁵P₃ C₂^tBu₂)₂] can ligate to other metal centres to afford novel bi- and tetrametallic complexes, whose structures have been elucidated by NMR and single crystal X-ray crystallographic studies.     

Synthesis and structures of mercury and cadmium complexes: [Ph4Sb] 2 + [Hg2I6]2−·Ph2Hg, [Ph4Sb] 2 + [E2I6]2− (E = Hg, Cd), and [Ph4Sb] 2 + [Hg4I10]2−

The reaction of pentaphenylantimony with mercury iodide affords the ionic complex [Ph₄Sb] ₂ ⁺ [Hg₂I₆]^2?·Ph₂Hg (I). The [Ph₄Sb] ₂ ⁺ [Hg₂I₆]^2? (II) and [Ph₄Sb] ₂ ⁺ [Cd₂I₆]^2? (III) complexes are synthesized from tetraphenylantimony iodide and mercury and cadmium iodides. The [Ph₄Sb] ₂ ⁺ [Hg₄I₁₀]^2? complex (IV) is prepared from tetraphenylantimony 2,4-dimethylbenzenesulfonate and mercury iodide. According to the X-ray diffraction data, the Sb atom in the [Ph₄Sb]⁺ cations of complex I has virtually ideal tetrahedral coordination (the CSbC angles are 108.09°–109.64°). In the central square fragment Hg₂I₂ of the [Hg₂I₆]^2? anion, the Hg-I_br bond lengths are 2.825 and 3.075 Å, and the terminal iodine atoms are more strongly bonded to the mercury atoms (Hg-I_term 2.691 and 2.700 Å). The [Cd₂I₆]^2? anion in complex III has a similar structure (the Cd-I_bridg and Cd-I_term distances are 2.865, 2.872 and 2.723, 2.748 Å, respectively). The anions in complex IV are joined by I…Hg (3.651 Å) and I…I (4.058 Å) interactions into an infinite dimeric network.     

Reactions of carbonyl clusters with potentially tridentate thioethers: Crystal and molecular structures of [Os4(CO) 13([12]aneS3)] and [Ru6(CO)15(μ4-η2- CO)([12]aneS3)] [([12]aneS3) = {(CH2) 3S}3]

The reaction of [Os₃(CO)₁₂ with [12]aneS₃ ([12]aneS₃  {(CH₂)₃S}₃) in octane for 6 h, under reflux, led to isolation of two products [Os₃(CO)₁₁([12]aneS₃)] (1) and [Os₄(CO) ₁₃([12]aneS₃)] (2), while with [Ru₃(CO)₁₂] under similar conditions, in THF, a number of products were obtained, including [Ru₄(CO)₁₁([12]aneS₃)] (3), [Ru₅(CO)₁₃([12]aneS₃)] (4), and [Ru₆(CO)₁₆([12]aneS₃)] (5). An X-ray diffraction study of 2 shows that the macrocycle is coordinated to the ‘wingtips’ of an Os₄ butterfly through the two electron pairs on one sulphur atom, while in 5 all three sulphur atoms of the macrocycle coordinate to two of the Ru atoms in a spiked edge-bridged tetrahedral metal framework.     

Synthesis and characterization by diffraction and 31P- and 77Se-NMR spectroscopy of [Mo3(μ3-Se)(μ2-Se2)3{N(SePPh2)2}3]Br and [Mo3(μ3-Se)(μ2-Se2)3{Se2P(OCH2CH3)2}3]Br

The new Mo/Se clusters [Mo₃(μ₃-Se)(μ₂-Se₂)₃{N(SePPh₂)₂}₃]Br (1) and [Mo₃(μ₃-Se)(μ₂-Se₂)₃{Se₂P(OCH₂CH₃)₂}₃]Br (2) have been synthesized by the selective substitution of the bromo ligands in the starting material [PPh₄]₂[Mo₃(μ₃-Se)(μ₂-Se₂)₃Br₆] with the selenoorgano bidentate ligands [N(SePPh₂)₂]^– and [Se₂P(OEt)₂]^–. The complexes have been characterized in solution by ³¹P- and ⁷⁷Se-NMR spectroscopy and in the solid state by single crystal X-ray diffraction; the same cation structures are present both in solution and in the solid state. Crystallographic data for 1: [Mo₃(μ₃-Se)(μ₂-Se₂)₃{N(SePPh₂)₂}₃]Br·3 CH₂Cl₂, C₇₂H₆₀BrMo₃N₃P₆Se₁₃·3 CH₂Cl₂, trigonal, space group R₃, a=21.299 (10) Å, c=38.433 (27) Å, V=15 100 (15) ų, T=−120 °C, Z=6; crystallographic data for 2: Mo₃(μ₃-Se)(μ₂-Se₂)₃{Se₂P(OCH₂CH₃)₂}₃]Br, C₁₂H₃₀BrMo₃P₃O₃Se₁₃, monoclinic, space group P2₁/n, a=13.404 (2) Å, b=22.732 (4) Å, c=13.932 (3) Å, β=113.134 (3)°, V=3 903.7(12) ų, T=−120 °C, Z=4. © 2000 Académie des sciences / Éditions scientifiques et médicales Elsevier SASphosphine ligands / amine ligands / phosphate ligands / selenium / molybdenum cluster / ⁷⁷Se-NMR spectroscopy     

The unusual stability of [NpO2Cl4]2−: Synthesis and characterisation of [NpO2(DPPMO2)2Cl]2[NpO2Cl4] and [Ph3PNH2]2[NpO2Cl4]

The [NpO₂(DPPMO₂)₂Cl][NpO₂Cl₄] complex (where DPPMO₂ = bis(diphenylphosphino)methanedioxide) contains the linear neptunyl group, {NpO₂}²⁺, with two bidentate P=O donor ligands. Coordinating anion Cl^? fills the fifth equatorial coordination site yielding a complex of general formula [NpO₂(DPPMO₂)₂X]₂[Y] (1) (where X = Cl^? and Y = [NpO₂Cl₄]^2?. Reaction between our newly prepared neptunium starting material [NpO₂Cl₂(thf)]_n and phosphinimine ligand produced crystals of [Ph₃PNH₂]₂[NpO₂Cl₄] (2). Compounds 1 and 2 have been structurally characterised.