Fluorination of [Os3(CO)12] and [Ir4(CO)12

Fluorination of [Os(3)CO(12)] in HF/SbF(5) affords [Os(CO)(4)(FSbF(5))(2)]. According to its crystal structure (orthorhombic, Pna2(1), a = 1590.3(3), b = 1036.6(1), c = 878.2(2) pm, Z = 4), the two SbF(6) units occupy cis positions in the octahedral environment around the Os atom. Fluorination of [Ir(4)(CO)(12)] in HF/SbF(5) produced three different compounds: (1) [Ir(4)(CO)(8)(mu-F)(2)(Sb(2)F(11))(2)] (tetragonal, P4n2, a = 1285.2(2), c = 952.9(1) pm, Z = 2). Here, two of the six edges of the Ir(4) tetrahedron in [Ir(4)CO(12)] are replaced by bridging fluorine atoms. (2) [fac-Ir(CO)(3)(FSbF(5))(2)HF]SbF(6).HF (orthorhombic, Pnma, a = 1250.6(1), b = 1340.7(2), c = 1092.6(2) ppm, Z = 4). The Ir(4) tetrahedron in Ir(4)(CO)(12) is completely broken down, but the facial Ir(CO)(3) configuration is retained. (3) [mer-Ir(CO)(3)F(FSbF(5))(2)] (triclinic, P1, a = 834.9(1), b = 86 4.9(1), c = 1060.0(1) pm, alpha = 69.173(4) degrees, beta = 77.139(4) degrees, gamma = 88.856(4) degrees, Z = 2).     

Halogenation behaviour of bidentate ligand-bridged derivatives of [Ru3(CO)12] and [Os3(CO)12]

Reaction of the ligand-bridged derivatives [M₃(CO)₁₀{μ-(RO)₂PN(Et)P(OR)₂}] and [M₃(CO)₈{μ-(RO)₂PN(Et)P(OR)₂}₂] (M = Ru or Os; R = Me or Prⁱ) with halogens leads to the formation of cationic products [M₃(μ-X)(CO)₁₀{μ- (RO)₂PN(Et)P(OR)₂}]⁺ and [M₃(μ-X)(CO)₈{μ-(RO)₂PN(Et)P(OR)₂}₂]⁺ (X = Cl, Br or I) in which the halogen bridges an opened edge of the metal atom framework; the crystal structure of [Ru₃(μ-I)(CO)₈{μ-(MeO)₂PN(Et)P(OMe)₂}₂]PF₆ is reported.     

Neue Phosphor-verbrückte Übergangsmetallcarbonyl-Komplexe Die Kristallstrukturen von [Re2(CO)7(PtBu)3], [Co4(CO)10(PtBu)2], [Ir4(CO)6(PtBu)6] und [Ni4(CO)10(PiPr)6]

New Phosphorus-bridged Transition Metal Carbonyl Complexes. The Crystal Structures of [Re₂(CO)₇(P^tBu)₃], [Co₄(CO)₁₀(P^tBu)₂], [Ir₄(CO)₆(P^tBu)₆], and [Ni₄(CO)₁₀(PⁱPr)₆], (P^tBu)₃ reacts with [Mn₂(CO)₁₀], [Re₂(CO)₁₀], [Co₂(CO)₈] and [Ir₄(CO)₁₂] to form the multinuclear complexes [M₂(CO)₇(P^tBu)₃] (M = Re ( 1 ), Mn ( 5 )), [Co₄(CO)₁₀(P^tBu)₂] ( 2 ) and [Ir₄(CO)₆(P^tBu)₆] ( 3 ). The reaction of (PⁱPr)₃ with [Ni(CO)₄] leads to the tetranuclear cluster [Ni₄(CO)₁₀(PⁱPr)₆] ( 4 ). The complex structures were obtained by X-ray single crystal structure analysis: ( 1 : space group P1 (Nr. 2), Z = 2, a = 917.8(3) pm, b = 926.4(3) pm, c = 1 705.6(7) pm, α = 79.75(3)°, β = 85.21(3)°, γ = 66.33(2)°; 2 : space group C2/c (Nr. 15), Z = 4, a = 1 347.7(6) pm, b = 1 032.0(3) pm, c = 1 935.6(8) pm, β = 105.67(2)°; 3 : space group P1 (Nr. 2), Z = 4, a = 1 096.7(4)pm, b = 1 889.8(10)pm, c = 2 485.1(12) pm, α = 75.79(3)°, β = 84.29(3)°, γ = 74.96(3)°; 4 : space group P2₁/c (Nr. 14), Z = 4, a = 2 002.8(5) pm, b = 1 137.2(8) pm, c = 1 872.5(5) pm, β = 95.52(2)°).     

Probing Surface Sites of TiO2: Reactions with [HRe(CO)5] and [CH3Re(CO)5]

Two carbonyl complexes of rhenium, [HRe(CO)₅] and [CH₃Re(CO)₅], were used to probe surface sites of TiO₂ (anatase). These complexes were adsorbed from the gas phase onto anatase powder that had been treated in flowing O₂ or under vacuum to vary the density of surface OH sites. Infrared (IR) spectra demonstrate the variation in the number of sites, including Ti⁺³? OH and Ti⁺⁴? OH. IR and extended X‐ray absorption fine structure (EXAFS) spectra show that chemisorption of the rhenium complexes led to their decarbonylation, with formation of surface‐bound rhenium tricarbonyls, when [HRe(CO)₅] was adsorbed, or rhenium tetracarbonyls, when [CH₃Re(CO)₅] was adsorbed. These reactions were accompanied by the formation of water and surface carbonates and removal of terminal hydroxyl groups associated with Ti⁺³ and Ti⁺⁴ ions on the anatase. Data characterizing the samples after adsorption of [HRe(CO)₅] or [CH₃Re(CO)₅] determined a ranking of the reactivity of the surface OH sites, with the Ti⁺³? OH groups being the more reactive towards the rhenium complexes but the less likely to be dehydroxylated. The two rhenium pentacarbonyl probes provided complementary information, suggesting that the carbonate species originate from carbonyl ligands initially bonded to the rhenium and from hydroxyl groups of the titania surface, with the reaction leading to the formation of water and bridging hydroxyl groups on the titania. The results illustrate the value of using a family of organometallic complexes as probes of oxide surface sites.     

Reaction of tetrakis (trifluoromethyl)allene with anions [CpMo(CO)2PPh3]- and [CpW(CO)2PPh3]

Conclusions The-dienyl complexes are formed when tetrakis (trifluoromethyl)allene is reacted with dicarbonyltriphenylphosphine--cyclopentadienylmolybdate and dicarbonyltriphenylphosphine--cyclopentadienyltungstate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 681–683, March, 1978.     

Topospecific Reactions of a [5.5.5.5]Fenestradiene with [Fe2(CO)9]

N, N-Dimethylformamide dimethyl acetal transforms an allylic OH group, which is part of a tetracyclic hydrocarbon in a unique elimination reaction into a [5.5.5.5]fenestradiene ( 2b → 4 ). In topologically selective reactions of this diene 4 with [Fe₂(CO)₉,], the [Fe(CO)₄(η²-diene)] and the [Fe(CO)3(η⁴-diene)] complexes 8 and 9 , respectively, are formed by complexation on one side of the diene moiety, whereas complexation on the other side leads to a [Fe(CO)₂(Cp)] complex 10 .     

Umsetzung von C(NMe2)4 mit Ni(CO)4 – Synthesen und Strukturen von [C(NMe2)3][(CO)3NiC(O)NMe2], [C(NMe2)3]2[Ni5(CO)12] und [C(NMe2)3]3[Ni6(CO)12][O2CNMe2]

Reaction of C(NMe₂)₄ with Ni(CO)₄ – Syntheses and Structures of [C(NMe₂)₃][(CO)₃NiC(O)NMe₂], [C(NMe₂)₃]₂[Ni₅(CO)₁₂], and [C(NMe₂)₃]₃[Ni₆(CO)₁₂][O₂CNMe₂] The reaction of C(NMe₂)₄ with Ni(CO)₄ in THF produces the carbamoyl complex [C(NMe₂)₃][(CO)₃NiC(O)NMe₂] ( 1 ); side products are the purple cluster compound [C(NMe₂)₃]₂[Ni₅(CO)₁₂] · THF ( 2 · THF) and the red cocristallization product [C(NMe₂)₃]₃[Ni₆(CO)₁₂][O₂CNMe₂] ( 3 ). All compounds were studied by X‐ray diffraction analyses. The cations of 3 are all disordered but not those of 1 and 2 . The unit cell of 1 contains two crystallographically independent anions (I and II) which differ in the dihedral angle between the plane of the carbamoyl ligand and the plane defined by the atoms C_Carbamoyl–Ni–CO amounting 0° in the anion I and 18° in the anion II.     

Syntheses of the new trinuclear ions [Ru3(CO)11]2− and [Os3(CO)11]2−

Stoichiometric reduction of Os₃CO)₁₂ and Ru₃(CO)₁₂ with K and Ca, respectively; yields the two new cluster dianions [Os₃(CO)₁₁]^2? and [Ru₃(CO)₁₁]^2? which have been isolated and characterized. Temperature-dependent ¹³C NMR spectra for [Os₃(CO)₁₁]^2? and infrared spectra of [Os₃(CO)₁₁]^2? and [Ru₃(CO)₁₁]^2? suggest a similar structure for these dianions in which there is a single edge-bridging carbonyl.     

Tellurium-bridged manganese carbonyl clusters: synthesis and structural transformations of [Te4Mn3(CO10]-, [Te2Mn3(CO)9]2-, [Te2Mn3(CO)9]-, and [Te2Mn4(CO)12]2-

The reactions of appropriate ratios of K2TeO3 and [Mn2(CO)10)] in superheated methanol solutions lead to a series of novel cluster anions [Te4Mn3(CO)10] (1), [Te2Mn3(CO)9]2- (2), [Te2Mn3(CO)9]- (3), and [Te2Mn4(CO)12]2- (4). When cluster 1 is treated with [Mn2(CO)10]/KOH in methanol, paramagnetic cluster 2 is formed in moderate yield. Cluster 2 is oxidized by [Cu(MeCN)4]BF4 to give the closo-cluster [Te2Mn3(CO)9]- (3), while treatment of 2 with [Mn2(CO)10]/KOH affords the closo-cluster 4. IR spectroscopy showed that cluster 1 reacted with [Mn2(CO)10] to give cluster 4 via cluster 2. Clusters 1-4 were structurally characterized by spectroscopic methods or/and X-ray analyses. The core structure of 1 can be described as two [Mn(CO)3] groups doubly bridged by two Te2 fragments in a mu2-eta2 fashion. Both [Mn(CO)3] groups are further coordinated to one [Mn(CO)4] moiety. Cluster 2 is a 49 e- species with a square-pyramidal core geometry. While cluster 3 displays a trigonal-bipyramidal metal core, cluster 4 possesses an octahedral core geometry.     

Diastereoselective [4 + 1] cycloaddition of alkenyl propargyl acetates with CO catalyzed by [RhCl(CO)2]2

A class of alkenyl propargyl acetates, RCH(OAc)C≡CC(CH(3))═CH(2) (5), are found to undergo [4 + 1] cycloaddition with CO (1 atm) in the presence of [RhCl(CO)(2)](2) in refluxing 1,2-dichloroethane to give cyclopentenones (6) in good yields. It has been demonstrated that, when the R group of 5 is a phenyl group bearing o-electron-withdrawing substituents, up to 10:1 diastereoselectivity and 96% yield can be achieved for the [4 + 1] cycloaddition. This process provides a convenient method to construct highly functionalized cyclopentenones that are useful in organic synthesis.     

The pentacoordinated [Cr(CO)5]2− dianion in [2,2,2‐crypt‐K]2[Cr(CO)5] ethylenediamine monosolvate

Bis[(4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane)potassium(+)] pentacarbonylchromate(2−) ethylenediamine monosolvate, [K(C₁₈H₃₆N₂O₆)]₂[Cr(CO)₅]·C₂H₈N₂, was obtained from the reaction between K₃Cd₂Sb₂ and Cr(CO)₆ in ethylenediamine in the presence of the macrocyclic 2,2,2‐crypt ligand. The structure provides the first crystallographic characterization of the pentacoordinated [Cr(CO)₅]²⁻ dianion. The central Cr^III atom is coordinated by five carbonyl ligands in a distorted trigonal–bipyramidal geometry. The distribution of the Cr—C bond lengths indicates a greater degree of back bonding from Cr^III to the equatorial carbonyl ligands compared with the axial carbonyl ligands.