Metallacyclic complexes with ortho-stannylated triphenylphosphine ligands, LnOs(κ(Sn,P)-SnMe2C6H4PPh2), derived from thermal reactions of the five-coordinate complex, Os(SnMe3)Cl(CO)(PPh3)2

Heating the five-coordinate trimethylstannyl complex, Os(SnMe₃)Cl(CO)(PPh₃)₂, in solution with triphenylphosphine induces an ortho-stannylation of one phenyl group of a triphenylphosphine ligand and an ortho-metallation of another triphenylphosphine ligand, to produce the metallacyclic complexes, Os(κ²(Sn,P)-SnMeClC₆H₄PPh₂)(κ²(C,P)-C₆H₄PPh₂)(CO)(PPh₃) (1) and Os(κ²(Sn,P)-SnMe₂C₆H₄PPh₂)(κ²(C,P)-C₆H₄PPh₂)(CO)(PPh₃) (2), suggesting the possible intermediacy of a complex with a coordinated stannylene ligand. Spectroscopic data indicate that only one diastereomer of 1 is formed and crystal structure determination of 1 reveals that this is the diastereomer with chloride directed towards the CO ligand. Complex 2 is converted to 1 through a redistribution reaction with SnMe₂Cl₂. Heating the six-coordinate trimethylstannyl complex, Os(SnMe₃)Cl(CO)₂(PPh₃)₂, in solution produces the osmium(II) methyl complex, Os(Me)(SnMe₂Cl)(CO)₂(PPh₃)₂ (3), through an exchange of methyl and chloride groups on the tin and osmium. In this rearrangement, the relative locations of the two CO ligands and the two PPh₃ ligands remains unchanged. However, when the six-coordinate trimethylstannyl complex, Os(SnMe₃)Cl(CO)₂(PPh₃)₂ is heated under CO, the same exchange reaction is observed but the mono-triphenylphosphine, tricarbonyl complex, Os(Me)(SnMe₂Cl)(CO)₃(PPh₃) (4), is produced and here the SnMe₂Cl ligand is located trans to the PPh₃ ligand. Crystal structure determinations for 1, 2, 3, and 4 have been obtained.     

The structurally characterised silyl complexes, Os(κ-S2CNMe2)(SiMeCl2)(CO)(PPh3)2 and Os(κ-S2CNMe2)(SiCl3)(CO)(PPh3)2, which have remarkably unreactive Si-Cl bonds

Treatment of Os(κ²-S₂CNMe₂)H(CO)(PPh₃)₂ with HSiMeCl₂ or HSiCl₃ gives in high yield Os(κ²-S₂CNMe₂)(SiMeCl₂)(CO)(PPh₃)₂ (1) or Os(κ²-S₂CNMe₂)(SiCl₃)(CO)(PPh₃)₂ (2), respectively. The crystal structures of both compounds have been determined and the Os-Si distances are 2.3672(10) Å for 1 and 2.3449(12) Å for 2. In solution, and under forcing conditions, both compounds are extraordinarily unreactive towards hydroxide ions.     

两个闭式十一顶钌硼烷簇合物[(PPh3)(p-BrC6H4CO2)2RuB10H8]和[(PPh3)2Ru(p-BrC6H4CO2)(PPh3)RuB10H9]的合成与晶体结构

[RuCl₂(PPh₃)₃],B₁₀H₁₀^2-与p-BrC₆H₄COOH在CH₂Cl₂中回流, 得到两个闭式十一顶钌十硼烷簇合物: [(PPh₃)(p-BrC₆H₄CO₂)₂RuB₁₀H₈] (1) 和 [(PPh₃)₂Ru(PPh₃)(p-BrC₆H₄CO₂)RuB₁₀H₉] (2), 并进行了元素分析、红外光谱、¹H核磁共振谱、¹³C核磁共振谱、X-射线单晶衍射表征. 簇合物1属于单斜晶系，空间群为C2/c, a = 2.569(4) nm, b=1.546(2) nm, c=1.927(3) nm, β=95.11(2)°, Z=8, V=7.622(21) nm³, D_c=1.533 Mg/m³, F(000)=3472, S=1.009, R=0.0418, wR=0.0775; 簇合物2属于三斜晶系, 空间群为P-1, a = 1.3142(3) nm, b=1.3761(3) nm, c=1.8503(4) nm, α=90.445(4)°, β=105.950(4)°, g=108.980(4)°, Z=2, V=3.0251(12) nm³, D_c=1.434Mg/m³, F(000)=1316, S=1.007, R=0.0464, wR=0.1175. 单晶结构分析表明, 两个簇合物的中心都具有一个闭式1:2:4:2:2堆砌结构的十一顶{RuB₁₀}金属硼烷骨架, 硼笼开口处具有船式构象的环状的六个硼原子对Ru(1)原子呈h⁶船式配位. 在簇合物1中, 钌原子有三个簇外配体, 一个三苯基膦, 两个对溴苯甲酸根. 对溴苯甲酸根上另外的两个氧原子分别取代了B(2)和B(3)上的氢原子, 从而在簇合物的两侧形成两个对称的Ru-O-C-O-B五员环. 簇合物2是一个双金属钌硼烷簇合物, Ru(2)通过一个Ru-Ru键和两个{RuH_mB}桥键与簇合物中心{RuB₁₀}相连, 从而在簇外形成了一个变形的Ru(1)-Ru(2)-B(3)-B(6)四面体结构.     

Synthesis of new chloro methyl niobium and tantalum complexes with silyl-cyclopentadienyl ligands: X-ray crystal structure of [Ta{η-C5H3(SiMe3)2}Cl2Me2]

Trichloro methyl [Nb{η⁵-C₅H₃(SiXMe₂)(SiMe₃)}Cl₃Me] (X = Cl, 2; Me, 3), dichloro dimethyl [Nb{η⁵-C₅H₃(SiXMe₂)(SiMe₃)}Cl₂Me₂] (X = Cl, 4; Me, 5) and tetramethyl [Nb{η⁵-C₅H₃(SiXMe₂)(SiMe₃)}Me₄] (X = Me, 6; Cl, 7) niobium complexes were synthesized by treatment of starting tetrachloro derivatives [Nb{η⁵-C₅H₃(SiXMe₂)(SiMe₃)}Cl₄] (X = Cl, 1a; Me, 1b) with dimethyl zinc or chloro methyl magnesium in different proportions and conditions. A mixture of trichloro methyl and dichloro dimethyl tantalum complexes [Ta{η⁵-C₅H₃(SiClMe₂)(SiMe₃)}Cl_4−xMe_x] (x = 1, 8; 2, 9) in a 2:1 molar ratio was obtained in the reaction of [Ta{η⁵-C₅H₃(SiClMe₂)(SiMe₃)}Cl₄] (1c) with 0.5 equivalents of ZnMe₂ in toluene at low temperature. 8 could be isolated as single compound when 1 equivalent of 1c was added to the mixtures of 8 and 9, while the reaction of 1c with 1.5 equivalents of dimethyl zinc gave 9 as unitary product. However, [Ta{η⁵-C₅H₃(SiMe₃)₂}Cl₄] (1d) reacts with 0.5 equivalents of alkylating reagent giving the trichloro methyl compound [Ta{η⁵-C₅H₃(SiMe₃)₂}Cl₃Me] (10) in good yield. On the other hand, [Ta{η⁵-C₅H₃(SiMe₃)₂}Cl₄] (1d) reacts with 2 equivalents of MgClMe in hexane at room temperature giving a mixture of dichloro dimethyl and chloro trimethyl complexes[Ta{η⁵-C₅H₃(SiMe₃)₂}Cl_4−xMe_x] (x = 2, 11; 3, 12), while the use of 4 equivalents of MgClMe converts 1c into the tetramethyl derivative [Ta{η⁵-C₅H₃(SiClMe₂)(SiMe₃)}Me₄] (13). Finally, a tetramethyl tantalum complex [Ta{η⁵-C₅H₃(SiMe₃)₂}Me₄] (14) was prepared by reaction of [Ta{η⁵-C₅H₃(SiXMe₂)(SiMe₃)}Cl₄] (X = Cl, 1c; Me, 1d) with 5 (X = Cl) or 4 (X = Me) equivalents of MgClMe in diethyl ether (X = Cl) or hexane (X = Me), respectively, as solvent. All the complexes were studied by IR and NMR spectroscopy and the molecular structure of the complex 11 was determined by X-ray diffraction methods.     

Palladium (II) complexes with mono-oxide 1,1′-bis(diphenylphosphino)metallocene ligands [Fe(η-C5Me4PPh2)(η-C5Me4P{O}Ph2)] and [Os(η-C5H4PPh2)(η-C5H4P{O}Ph2)]

The monoxides [Fe(η⁵-C₅Me₄PPh₂)(η⁵-C₅Me₄P{O}Ph₂)] (1) and [Os(η⁵-C₅H₄PPh₂)(η⁵-C₅H₄P{O}Ph₂)] (2) have been prepared by treatment of the corresponding diphosphines with CCl₄ and methanol.These ligands react with [Pd(PhCN)₂Cl₂] to give dichloride complexes of different structure.The dimeric complex [{Os(η⁵-C₅H₄PPh₂)(η⁵-C₅H₄P{O}Ph₂)}PdCl(μ-Cl)]₂ (4) contains the monodentate P-coordinated osmocene ligand with the free P{O}Ph₂ group, while the octamethylferrocene ligand gives the chelate k²-P,O complex [{Fe(η⁵-C₅Me₄PPh₂)(η⁵-C₅Me₄P{O}Ph₂)}PdCl₂] (3).The structures of 3 and 4 have been determined crystallographically.Treatment of 3 and 4 with silver salts in CH₂Cl₂ or acetonitrile leads to the corresponding dicationic complexes[{M(η⁵-C₅R₄PPh₂)(η⁵-C₅R₄P{O}Ph₂)}Pd(MeCN)_x]²⁺ (5, M = Fe, R = Me; 6, M = Os, R = H). Complex 5 decomposes upon isolation, in contrast 6 is rather stable, probably due to Os-Pd bonding. The dichlorides 3 and 4 catalyze catalytic amination of p-bromotoluene with N-(4-tolyl)morpholine with lower activity than (dppf)PdCl₂, however they perform comparable to (dppf)PdCl₂ activity in coupling of p-bromotoluene with p-methoxyphenyl boronic acid.     

Stable radical adducts of diisopropylphosphoryl radicals with fullerene complexes (η2-C60)Os(CO)(PPh3)2(CNBut) and (η2-C70)Os(CO)(PPh3)2(CNBut)

It was determined by ESR spectroscopy that the UV irradiation of toluene solutions containing Hg[P(O)(OPrⁱ)₂ and the complex (²-C₆₀)Os(CO)(PPh₃)₂(CNBu^t) produces six stable regioisomeric adducts of phosphoryl radicals with complexes, which are not demetallated under UV irradiation and do not dimerize in the absence of UV irradiation. This is caused by the addition of the phosphoryl radicals to the carbon atoms of fullerene localized near the metal-containing moiety. The addition of the phosphoryl radicals to (²-C₇₀)Os(CO)(PPh₃)₂(CNBu^t) gives rise to the formation of nine stable regioisomeric radical adducts. A comparison of the composition of regioisomers of the radical adducts of C₇₀ with the phosphoryl radicals, which were formed directly from C₇₀ and from the radical adducts of ²-C₇₀)Os(CO)(PPh₃)₂(CNBu^t) by the demetallation of the latter, revealed an orienting effect of the osmium-containing moiety on the addition of the phosphoryl radicals to the fullerene complex.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1968–1972, September, 2004.     

The preparation and crystal structure of (η-C5H5)(OC)3Mo(CH2)3C6H5

The reaction of with p-CH₃C₆H₄S(O)₂O(CH₂)₃C₆H₅ produces (η⁵-C₅H₅)(OC)₃Mo(CH₂)₃C₆H₅. This is only the second structurally characterized organometallic species in which an aromatic moiety is separated by three or more methylene groups. The alkyl chain adopts a staggered conformation, the Mo-C(1)-C(2)-C(3)-C(4) unit is nearly coplanar, and the alkyl chain eclipses the trans-carbonyl group on Mo. NMR evidence indicates that this conformation is preserved in solution.     

Synthesis of electronically and coordinatively unsaturated complexes [Ru2(CO)4(μ-H)(μ-PBu2)(μ-L2)] (L2 = biphosphanes)

A convenient synthesis and the characterization of six new electronically and coordinatively unsaturated complexes of the formula [Ru₂(CO)₄(μ-H)(μ-P^tBu₂)(μ-L₂)] (2b-g) (RuRu) is described exhibiting a close relation to the known [Ru₂(CO)₄(μ-H)(μ-P^tBu₂)(μ-dppm)] (2a). The complexes 2b-g were obtained in a kind of one-pot synthesis starting from [Ru₃(CO)₁₂] and P^tBu₂H in the first step followed by the reaction with the bidentate bridging ligand in the second step. The method was developed for the following bridging ligands (μ-L₂): dmpm (2b, dmpm = Me₂PCH₂PMe₂), dcypm (2c, dcypm = Cy₂PCH₂PCy₂), dppen (2d, dppen = Ph₂PC(=CH₂)PPh₂), dpppha (2e, dpppha = Ph₂PN(Ph)PPh₂), dpppra (2f, dpppra = Ph₂PN(Pr)PPh₂), and dppbza (2g, dppbza = Ph₂PN(CH₂Ph)PPh₂). The molecular structures of all new complexes 2b−g were determined by X-ray diffraction.     

Thiolate-bridged heterometallic complexes of manganese and platinum: Synthesis and molecular structures of (CO)4Mn(μ-SPh)Pt(PPh3)2, (CO)3(PPh3)Mn(μ-SPh)Pt(PPh3)(CO), and (CO)3Mn(μ-SPh)Pt(PPh3)(Dppm)

A reaction of the dimer [Mn(CO)₄(SPh)]₂ with (PPh₃)₂Pt(C₂Ph₂) gave the heterometallic complex (CO)₄Mn(μ-SPh)Pt(PPh₃)₂ (I) and its isomer (CO)₃(PPh₃)Mn(μ-SPh)Pt(PPh₃)(CO) (II). A reaction of complex I with a diphosphine ligand (Dppm) yielded the heterometallic complex (CO)₃Mn(μ-SPh)Pt(PPh₃)(Dppm) (III). Complexes I–III were characterized by X-ray diffraction. In complex I, the single Mn-Pt bond (2.6946(3) ?) is supplemented with a thiolate bridge with the shortened Pt-S and Mn-S bonds (2.3129(5) and 2.2900(6) ?, respectively). Unlike complex I, in complex II, one phosphine group at the Pt atom is exchanged for one CO group at the Mn atom. The Mn-Pt bond (2.633(1) ?) and the thiolate bridge (Pt-S, 2.332(2) ?; Mn-S, 2.291(2) ?) are retained. In complex III, the Mn-Pt bond (2.623(1) ?) is supplemented with thiolate (Pt-S, 2.341(2) ?; Mn-S, 2.292(2) 0?) and Dppm bridges (Pt-P, 2.240(1)?; Mn-P, 2.245(2) ?). Apparently, the Pt atom in complexes I–III is attached to the formally double bond , as in Pt complexes with olefins.     

Synthesis and structural characterisation of five copper(I) and silver(I) complexes with 2-aminopyridine (2-APy), [Cu(μ-Cl)(2-Apy)(PPh3)]2, [Ag(μ-X)(2-Apy)(PPh3)]2 (X = Cl,Br), [Ag(μ-ONO2)(2-Apy)(EPh3)]2 (E = P,As)

Five new copper(I)/silver(I) complexes containing 2-aminopyridine, [Cu(μ-Cl)(2-Apy)(PPh₃)]₂(1), [Ag(μ-Cl)(2-Apy)(PPh₃)]₂(2), [Ag(μ-Br)(2-Apy)PPh₃)]₂(3), [Ag(μ-ONO₂)(2-Apy)(PPh₃)]₂(4), [Ag(μ-ONO₂)(2-Apy)(AsPh₃)]₂(5) have been synthesised for the first time. Complexes 1–5 are obtained by the reactions of MX (MX = CuCl for 1; M = Ag for 2–5; X = Cl, Br for 2–3; X = NO₃ for 4–5) with the monodentate ligands EPh₃ (E = P for 1–4; E = As for 5) and 2-Apy in the molar ratio of 1:1:2 in the mixed solvent of CH₂Cl₂ and MeOH. Complexes 1–5 are characterised by IR and X-ray diffraction. In 1–5, chloride, bromide and nitrate ions bridge two metal atoms to form dinuclear complexes containing the parallelogram cores M₂X₂ (M = Cu, Ag).     

Binuclear iridium complexes containing bridging 1,2-dicarba-closo-dodecaborane-1,2-dichalocogenolato ligands: Molecular structures of the complexes [(CODIr)2(μ2-S2C2(B10H10))] and [(CpIr)2(μ2-Se2C2(B10H10))]

Four binuclear iridium complexes with a chelating 1,2-dicarba-closo-dodecaborane-1,2-dichalcogenolate ligands [Ir₂(COD)₂(μ₂-E₂C₂B₁₀H₁₀)] [E = S (3a), Se (3b)] [(Cp^∗Ir)₂(μ₂- E₂C₂B₁₀H₁₀)] [E = S (5a), Se (5b)] have been synthesized through different method. The formal oxidation state of iridium in complexes 3 and 5 are I and II, respectively, due to the different electron donor coordinated to the iridium center. All four complexes 3a-5b are characterized by IR, ¹H, ¹³C, ¹¹B NMR spectra and elemental analyses. The molecular structures of complex 3a and 5b have been determined by X-ray crystallographic analysis, only 5b shows the metal-metal interaction between the two iridium atoms.     

Diverse coordination of two ligands in ferromagnetic [Cu(μ-HCO2)2(3-pyOH)]n and [Cu2(μ-HCO2)2(μ-3-pyOH)2(3-pyOH)2(HCO2)2]n

Two novel polynuclear complexes with methanoate anions and 3-hydroxypyridine ligands [Cu(μ-HCO₂)₂(3-pyOH)]_n (1) and [Cu₂(μ-HCO₂)₂(μ-3-pyOH)₂(3-pyOH)₂(HCO₂)₂]_n (2), respectively, were synthesized and characterized. The central copper atom in 1 is surrounded by four methanoates and a 3-pyOH molecule, forming a square-pyramidal CuO₃NO chromophore. All the methanoates are bidentate and serve as bridges between the adjacent copper ions via syn-anti and anti–anti coordination. The basal square coordination axes are formed by O(syn), N(3-pyOH) (1.974(2), 2.016(2) Å) and O(anti), O(anti) (1.945(2), 1.960(2) Å), while the third O(anti) (2.247(2) Å) is on the top of the pyramid. A ferromagnetic transition with an exchange constant 2J/k_B = 9.2 cm⁻¹ is found for 1 below 20 K. This interaction probably takes place through two syn-anti methanoates extended in a chain through the 2D structure. On the other hand, two monoatomic Cu–O–Cu intra-dinuclear asymmetric (1.986(2), 2.415(2) Å) bridges of two methanoates in [Cu₂(HCO₂)₄(3-pyOH)₄] (2) are present. An elongated distorted octahedral coordination sphere around each copper(II) atom is completed by an additional monodentate terminal methanoate (1.975(2) Å), two N-coordinated 3-pyOH (2.005(2), 2.002(2) Å) and the third weakly O-coordinated 3-pyOH (2.732(2) Å). Although a shorter Cu?Cu distance is noticed in 2 than in 1 (4.690(1) Å 1, 3.442(1) Å 2), much weaker ferromagnetism is found in 2.     

Reactions of [Fe3Cp2(CO)3(μ-CO)(μ3-CO)(μ3-CF3C2CF3)] with diphosphines: X-ray structure of a complex in which two tri-iron clusters are linked only by Ph2PCH2CH2PPh2

Reactions of the trinuclear iron cluster [Fe₃Cp₂(CO)₃(μ-CO)(μ₃-CO)(μ₃-CF₃C₂CF₃)] (1) with the bis(phosphino) ligands dppm and dppe give different results: dppe yields mainly the hexanuclear compound (2) in which two tri-iron cluster units are linked by the diphosphine, although a trinuclear derivative (3) with a chelating dppe ligand is also obtained as a minor product, whereas dppm displaces carbonyl to give complexes containing exclusively a single tri-iron unit, though the phosphine may be either dangling (4) or chelating (5). The complexes 2-5 have been characterised by elemental analyses and from their IR and NMR spectra, supplemented in the case of 2 by a single crystal X-ray diffraction analysis.     

X-ray and conformation analysis of the new trinuclear cluster of osmium Os3(μ,η2-OCC6H5)(η3-C3H5)(CO)9

The crystal structure of the Os₃(μ,η²-O=CC₆H₅)(η³-C₃H₅)(CO)₉ cluster synthesized by the reaction of the (μ-H)Os₃(μ-O=CC₆H₅)(CO)₁₀ complex with allylamine in chloroform was determined by X-ray analysis. Prolonged storage of the reaction mixture led to N-C bond cleavage in allylamine and η³-addition of the allyl fragment at one of the Os atoms (Os-C 2.246 ?, 2.248 ?, and 2.273 ?). The unit cell parameters of the complex are a = 9.494(1) ?, b = 10.479(1) ?, c = 12.474(2) ?, α = 84.55(1)°, β = 70.08(1)°, γ = 70.72(1)°, V = 1255.8(4), ?³, space group P , Z = 2; C₁₉H₁₀O₁₀Os₃; d _calc = 2.922 g/cm³, 3085 I _hkl > 2σ _I of 3611 collected reflections; R = 0.0252. The structure of Os₃(μ,η²-O=CC₆H₅)(η³-C₃H₅)(CO)₉ is molecular. The plane of the Os₃ triangle and the OsCOOs plane are connected according to the “butterfly” principle with an angle of 103.4° between them. The Os-Os distances in the cluster core vary from 2.836(1) ? to 2.844(1) ?; the Os-C_carb distances are 1.88(1)–1.97(1) ?; the distances to the atoms of the bridging ligands are Os-C 2.11(1) ?, Os-O 2.14(1) ?; the O-C bridging bond is 1.24(1) ?. of the Os₃(μ,η²-O=CC₆H₅)(η³-C₃H₅)(CO)₉ triosmium cluster were studied theoretically. The potential curve of the internal rotation of the allyl ligand relative to the Os(1)-C(9) bond was determined. The rotation barrier of the allyl ligand in crystal relative to the Os(1)-C(9) bond is 8.38 kJ/mol, and the rotation of the ligand is not hindered. The effects of the intra-and intermolecular interactions on the conformation state of the cluster complex are considered. Original Russian Text Copyright ? 2008 by V. A. Maksakov, N. V. Pervukhina, N. V. Podberezskaya, M. Yu. Afonin, V. A. Potemkin, and V. P. Kirin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 5, pp. 926–932, September–October, 2008.     

Syntheses and characterization of η-cyclopentadienyl and η-indenyl ruthenium(II) complexes of arylazoimidazoles: The molecular structure of the complex [(η-C5H5)Ru(PPh3)(C6H5-NN-C3H3N2)]

The complex [(η⁵-C₅H₅)Ru(PPh₃)₂Cl] (1) reacts with several arylazoimidazole (RaaiR′) ligands, viz., 2-(phenylazo)imidazole (Phai-H), 1-methyl-2-(phenylazo)imidazole (Phai-Me), 1-ethyl-2-(phenylazo)imidazole (Phai-Et), 2-(tolylazo)imidazole (Tai-H), 1-methyl-2-(tolylazo)imidazole (Tai-Me) and 1-ethyl-2-(tolylazo)imidazole (Tai-Et), gave complexes of the type [(η⁵-C₅H₅)Ru(PPh₃)(RaaiR′)]⁺ {where R, R′ = H (2), R = H, R′ = CH₃ (3), R = H, R′ = C₂H₅ (4), R = CH₃, R′ = H (5), R, R′ = CH₃ (6), R = CH₃, R′ = C₂H₅ (7)}. The complex [(η⁵-C₉H₇)Ru(PPh₃)₂(CH₃CN)]⁺ (8) undergoes reactions with a series of N,N-donor azo ligands in methanol yielding complexes of the type [(η⁵-C₉H₇) Ru(PPh₃)(RaaiR′)]⁺ {where R, R′ = H (9), R = H, R′ = CH₃ (10), R = CH₃, R′ = H (11), R = CH₃, R′ = C₂H₅ (12)}, respectively. These complexes were characterized by FT IR and FT NMR spectroscopy as well as by analytical data. The molecular structure of the complex [(η⁵-C₅H₅)Ru(PPh₃)(C₆H₅-NN-C₃H₃N₂)]⁺ (2) was established by single crystal X-ray diffraction study.     

双胺配体[K2(L)(THF)2](L=Ph2Si(NAr)2, Ar=2, 6-iPr2C6H3) 构筑的两个低价稀土镱化合物

以双胺类配体[K₂(L)(THF)₂] (1)(L=Ph₂Si(NAr)₂, Ar=2, 6-ⁱPr₂C₆H₃)与二价稀土YbI₂(THF)₂的交换反应得到2个不同类型的化合物[Yb(L)(THF)₃] (2)和{Yb(L)₂[K(THF)₂]₂} (3)。对化合物进行X-射线单晶结构解析, 核磁共振和元素分析表征。研究结果表明：化合物2中, 通过1个双齿含氮配体和3个中性THF分子配位, 以五配位模式稳定二价镱稀土中心。而化合物3中二价稀土镱是与2个螯合胺类配体配位, 以共平面、四配位模式稳定其金属中心。K+恰好在配体的2个苯环之间, 形成独特的三明治结构, 有助于化合物的稳定。     

Bridging allyl ligands upon allene insertion into electron-deficient triosmium-hydride clusters [Os3(CO)9(μ3-NSC7H3R)(μ-H)] (R = H, Me)

Allene reacts with the benzothiazolide clusters [Os₃(CO)₉(μ₃-NSC₇H₃R)(μ-H)] (R = H, Me) to afford the bridging allyl complexes [Os₃(CO)₇(μ-CO)₂(μ-NSC₇H₃R)(μ-η¹:η²:η¹-CH₂CHCH₂)] resulting from insertion of allene into the metal-hydride. Both have been crystallographically characterized and differ with respect to the relative arrangement of allyl and benzothiazolide at the triosmium centre.     

Synthesis and crystal structure of highly soluble ansa-titano- and zirconocene dichloride complexes [Me2Si(η-C5H2(SiMe3)2]2MCl2 (M=Ti, Zr)

The synthesis and X-ray characterization of ansa-metallocene dichloride titanium and zirconium complexes of the type [Me₂Si(η⁵-C₅H₂(SiMe₃)₂)₂]MCl₂ (M=Zr (1), Ti (2)) are reported. The complexes have been tested for ethylene polymerization.