Reaction of Mo(CO)6 with Alkoxide: Synthesis and Structure of the Mo(0)-OR Complex [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2C6H5)3]

The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo(0) compound [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2- C6H5)3] 1. 1 crystallizes in monoclinic, space group P21/c with a=15.359(2), b=18.378(3), c=24.952(2)(A), β=102.268(4)°, V=6882.3(16) (A)3, Mr=1348.34, Z=4, Dc=1.301 g/cm3, F(000)=2832 and μ= 0.424 mm-1. The final R=0.0606 and wR=0.1552 for 9396 observed reflections (Ⅰ ＞ 2σ(Ⅰ)). 1 contains a [Mo2O3]3- core in triangular bi-pyramidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three μ-O atoms from C6H5CH2OC6H4O- bridging ligands. The Mo…Mo distance is 3.30(8) (A), indicating no metalmetal bonding. A formation pathway via forming a di-molybdenum(0) di-bridging OR compound [Mo2(μ-OR)2(CO)8]2- has been figured out and the reaction of Mo(CO)6 with alkoxide has also been discussed.     

Spectroelectrochemical studies of [Mo(dtc)_4][Eu(dtc)_4] and [Mo(dtc)_4][Er(dtc)_4]

Redox and spectroscopic properties of the eight-coordination complexes of molybdenum and the rare-earth elements Eu or Er with N,N-diethyldithiocarbamate (dtc) were characterised by cyclic voltamrnetry and UV-visible absorption spectra.The complex cation [Mo(dtc)4]+ is more stable than the complex anions [Eu(dtc)4]-and [Er(dtc)4]-in redox processes,and possesses good redox reversibility.The electron transfer number,formal standard electrode potential in the redox process for the complex cation and its diffusion coefficients were obtained by in aitu spectroelectro-chemistry.     

Diamagnetic anisotropy of quadruple MoMo bonds: α-Mo2Cl4(diphosphine)2 complexes

Two components (χ_xV — χ′_hu and χ_xV — χ″_hu) of magnetic anisotropy of MoMo quadruple bonds have been obtained by using the X-ray crystallographic molecular structure and the low temperature ¹H NMR spectrum of α-Mo₂Cl₄[(C₆H₅)₂PCH₂CH₂P(p-RC₆H₄)₂]₂ [R  H (dppe), CH₃ (dpdt) and tert-C₄H₉ (dpdbp)]. The values of χ_xV — χ′_hu and χ_xV — χ″_hu for the dpdbp case are −(8470 ± 200) x 10⁻³⁶ and −(5540 ± 70) x 10⁻³⁶ m³ molecule⁻¹, respectively, which are several times as large as χ_xV — χ_hu (Mo³Mo). Through detailed examination of the ¹H NMR signals of the ethylene protons, conformational flexing of the chelate rings of α-Mo₂Cl₄(dpdbp)₂ has been recognized.     

Biomimetic Epxidation of Alkenes by Phenyliodonium Diacetate [PhI(OAc)_2] in the Presence of Mn(Ⅲ) Complex of meso-Tetrakis(4-methoxyphenylporphyrin) Acetate Mn[(T4-OCH_3P)P]OAc

We have reported that phenyliodonium diacetate[PhI(OAc)2] can serve as an eco-friendly mild oxidant for the epoxidation of alkenes in the presence of Mn(III) complex of meso-tetrakis(4-methoxyphenylporphyrin) acetate Mn[(T4-OCH3P)P]OAc and imidazole in CH2Cl2.The amounts of the products(%) and selectivities are very dependent upon the electronic and steric properties of the starting alkenes.To evaluate the validity of this catalytic system for C H activation,cyclohexane and ethylbenzene were oxidized under ...     

Synthesis and structure of two molybdovanadates containing coordinatively bound oxalato ligands: (NH4)6[Mo6V2O24(C2O4)2]·6H2O and (NH4)4[H2Mo2V2O12(C2O4)2]·2H2O

The compounds (NH₄)₆[Mo₆V₂O₂₄(C₂O₄)₂]·6H₂O (I) and (NH₄)₄[H₂Mo₂V₂O₁₂(C₂O₄)₂]·2H₂O (II) have been prepared from molybdenum(VI) oxide and ammonium vanadate in aqueous solution through the addition of ammonium oxalate, and their structures determined by X-ray structure analysis. Whereas the molybdovanadate anion [Mo₆V₂O₂₄(C₂O₄)₂]⁶⁻ found in (I) consists of six MoO₆ and two VO₆ edge-sharing octahedra of the γ-[Mo₈O₂₆]⁴⁻ type structure, the tetranuclear anion [H₂Mo₂V₂O₁₂(C₂O₄)₂]⁴⁻ of (II) adopts the structure with a M₄O₁₆ core. Both complexes contain bidentate oxalato ligands bonded to the vanadium ions. In both crystal structures the molybdovanadate anions are mutually hydrogen bonded by ammonium ions and water molecules.     

The formation of alkyne and alkynyl complexes by reaction of 1-alkynes with trans-[M(N2)2(PH2PCH2CH2PPh2)2] (M  Mo OR W) and with [Mo(Ph2PCH2PPh2)3]: X-ray structure of trans-[Mo(CCPh)2(PH2PCH2CH2PPh2)2]

Reaction of RCCH (R  Ph, CO₂Meor CO₂Et) with trans-[M(N₂)₂(dppe)₂] (M  Mo or W; dppe  Ph₂PCH₂CH₂PPh₂) or [Mo(dppm)₃] (dppm  Ph₂PCH₂PPh₂) gives the alkyne complexes [M(RCCH)₂(diphos)₂] (diphos  dppe, M  Mo, R = Ph; dihpos  dppm, M  Mo, R  Ph or CO₂Me) and the alkynyl complexes trans-[M(cCR)₂(dppe)₂], [MH₂(CCR)₂ (dppe)₂] (M  Mo or W. R  Ph, CO₂Me or CO₂Et) and cis-[WH(CCCO₂Me)(dppe)₂]: the X-ray structure of trans-[Mo(CCPh)₂(dppe)₂] is reported.     

Ligand shift in mixed-cluster complexes: synthesis of alkyne-bridged Co2Mo2 clusters with two triply-bridging sulphur atoms: crystal structure of [Co2Mo2(η5-Cp)2(μ3-S)2(μ4-CF3C2Me)(CO)4]

Reaction of the complexes [(CO)₃Co(μ-RC₂R′)Co(CO)₃] (R = R′ = CF₃; R = Ph, CF₃ and R′ = H) with the MoMo dinuclear derivative [Mo₂Cp₂(μ-SMe)₂(CO)₂] leads to cleavage of both CS and CH bonds with the formation of closo-octahedral Mo₂CO₂C₂ clusters stabilised by a μ₄-η²-bound alkyne. An X-ray diffraction study has shown that the two Mo₂Co faces of the octahedron are capped by triply-bridging sulphur atoms.     

Photochemistry of (Me3P)4Mo(η-CO2)2: Deoxygenation of coordinated carbon dioxide and phosphine oxidation

Irradiation of the title compound 1 through quartz in toluene solution at − 20°C produces cis-Mo(CO)₂(PMe₃)₄ and OPMe₃ as the major products along with lesser amounts of mer- and _fac-Mo(CO)₃(PMe₃)₃ and Mo(CO)PMe₃) ₅. Irradiation of 1 through Pyrex produces in addition substantial amounts of an unstable species formulated as trans-Mo (CO)₂(PMe₃)₄.     

Syntheses and characterization of new MnII and FeII complexes with 4′-(4-pyridyl)-2,2′ : 6′,2″-terpyridine (pyterpy), [Mn(pyterpy)(MeOH)2(OAc)](ClO4) and [Fe(pyterpy)2](SCN)2 · MeOH

Two new Mn^II and Fe^II complexes with 4′-(4-pyridyl)-2,2′ : 6′,2″-terpyridine (pyterpy), [Mn(pyterpy)(MeOH)₂(OAc)](ClO₄) (1) and [Fe(pyterpy)₂](SCN)₂ · MeOH (2) have been synthesized and characterized by CHN elemental analysis, IR spectroscopy, and structurally analyzed by single-crystal X-ray diffraction. The thermal stabilities of these compounds were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The potentially tetradentate pyterpy ligand is a tridentate donor to both Mn(II) and Fe(II). The non-coordinated pyridyl interacts via O–H ··· N and C–H ··· N hydrogen bonds with adjacent molecules in 1 and 2, respectively, to form inversion symmetric dimers. Compound 1 is further extended into infinite hydrogen bonded chains via pairs of O–H ··· O_acetate hydrogen bonds.     

Mixed-ligand cluster [Mo3S4(Dtp)2(μ-AcO)Cl(Me2Bipy)]: Synthesis and structure

Mixed-ligand cluster [Mo₃S₄(Dtp)₂(μ-AcO)Cl(Me₂Bipy)] · CHCl₃ (I · CHCl₃), where Dtp is (EtO)₂PS₂, was synthesized by the reaction of the molybdenum aqua complex [Mo₃S₄(H₂O)₉]⁴⁺ with 4,4′-dimethyl-2,2′-bipyridine (Me₂Bipy) and phosphorus sulfide (P₄S₁₀) in ethanol followed by chromatographic separation on silica gel and crystallization in the presence of acetic acid. The crystal structure of I · CHCl₃ was determined by X-ray diffraction analysis. The synthesized compound was characterized by the IR and NMR spectra and elemental analysis. The electronic structure of the synthesized compound was established, and its electrochemical behavior in a solution was studied.     

Reactivity of Mo3PdS4+ 4 Cluster: Evidence for New Ligands PhP(OH)2 and Ph2P(OH) and Structural Characterization of [Mo3(Pd(PPh3))S4(H2O)5Cl4]⋅0.5CH3OH⋅3H2O

Cuboidal cluster aqua complex [Mo₃(PdCl)S₄(H₂O)₉]³⁺ in 4M HCl causes isomerization of (HO)₂P(O)(H), (HO)P(O)(H)₂, PhP(O)(OH)(H), and Ph₂P(O)(H) into hydroxo tautomers P(OH)₃, HP(OH)₂, PhP(OH)₂, and Ph₂P(OH) which are stabilized by P coordination to the Pd atom in the cluster. The reactions were followed by ³¹P NMR and UV/Vis spectroscopy. Hypophosphorous acid H₂P(O)(OH) in the presence of the cluster is rapidly oxidized into phosphorous acid; the reaction can be made catalytic. Coordination of PPh₃ also takes place, giving [Mo₃(Pd(PPh₃))S₄(H₂O)₅Cl₄]0.5CH₃OH3H₂O, whose crystal structure was determined.     

Synthesis, Characterization and Crystal Structure of [Co2Mo2(μ4-C2HPh)(μ-CO)4(CO)4(η5-C5H4C(O)Me)2]

The reaction of μ-alkyne-bridged dimolybdenum compound [Mo2(μ-C2HPh)(CO)4(η5-C5H4C(O)Me)2] 1 with Co2(CO)8 in refluxing toluene gave a new butterfly compound [Co2Mo2(μ4-C2HPh)(μ-CO)4(CO)4(η5-C5H4C(O)Me)2] 2 which was fully characterized by elemental analysis, IR, 1H NMR and X-ray single crystal diffraction techniques. 2 crystallized in monoclinic system, C30H20Co2Mo2O10, Mr=850.23, space group P21/a(#14), a=14.165(5), b=12.498(2), c=16.204(2)(A), β = 96.50(2)°, V = 2850(1)(A)3, Z = 4, Dc = 1.981 g cm-3, F(000)=1672, μ(MoKα)=20.41 cm-1, final R=0.030, Rw=0.039 for 4831 observable reflections with I>2σ(I). The structure contains a Co2Mo2 butterfly core, and each Mo-Co bond is spanned by an asymmetric semi-bridging carbonyl ligand.     

Reaction of Mo(CO)_6 with Alkoxide: Synthesis and Structure of the Mo(0)-OR Complex [Et_4N]_3[Mo_2(CO)_6(μ-OC_6H_4OCH_2C_6H_5)_3]

The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo(0) compound [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2- C6H5)3] 1. 1 crystallizes in monoclinic, space group P21/c with a = 15.359(2), b = 18.378(3), c = 24.952(2), β = 102.268(4)°, V = 6882.3(16) 3, Mr = 1348.34, Z = 4, Dc = 1.301 g/cm3, F(000) = 2832 and μ = 0.424 mm-1. The final R = 0.0606 and wR = 0.1552 for 9396 observed reflections (I > 2σ(I)). 1 contains a [Mo2O3]3- core in triangular bi-pyramidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three μ-O atoms from C6H5CH2OC6H4O- bridging ligands. The Mo…Mo distance is 3.30(8) , indicating no metal- metal bonding. A formation pathway via forming a di-molybdenum(0) di-bridging OR compound [Mo2(μ-OR)2(CO)8]2- has been figured out and the reaction of Mo(CO)6 with alkoxide has also been discussed.     

STRUCTURE OF {Mo4S4（μ—OAc）2[S2P（OC2H5）2]4H}

<正> {Mo4S4(μ-OAc)2(dtp)4H}3,(dtp=S2P(OEt)2),Mr=1371.60,Or-thorhombic, space group Pcab, a = 18. 90 (2) ,b = 21. 678 (4 ) , c = 24. 491 (4 ) A , V = 10031(7)A3,Z=8,Dc=1.818g/cm-3,F(000)=5464,λ(MoKa)=0.71073A,finalR= 0. 069 for 3738 independent reflections. This is a successful example of the formation of [Mo4S4]5+ from[3+1] reaction mode. The results of the structure determination indicate that the configuration of the title compound exhibits a tetranuclear cubane-type core [Mo4S4]5+ with six Mo - Mo distances in the range 2. 685~2. 969A and is very similar to that of the previously characterized compound {Mo4S4(μ-OAc)2(dtp)4}2, [Mo4S4]6+, which was obtained directly by the reaction of MoCl3·3H2O with dtp. Some notable differences, however, can be found when six Mo - Mo bond distances and bonding parameters of the four terminal bidentate ligands (dtp) are compared between these two compounds , That can be attributed to the difference in the oxidation state of these two clusters .     

Synthesis and Crystal Structure of [H-amp]4[Mo8O26(DMF)2]·2H2O (amp = 2-Amino-6-methyl-pyridine)

The reaction of MoO2(acac)2 with 2-amino-6-methyl-pyridine (amp) in the mixed solvent of DMF (N,N-dimethylformamide) and water affords the title complex [H-amp]4- [Mo8O26(DMF)2]·2H2O which was characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction analysis with the following crystallographic data: C30H54Mo8N10O30, Mr = 1802.35, monoclinic, P21/n, a = 8.631(1), b = 24.260(3), c = 13.351(2)A,β= 104.688(3)°, V = 2704.2(7) A3, Z = 2, Dc = 2.213 g/cm3, μ =1.890 mm－1 and F(000) = 1760. The final R = 0.0281 and Wr = 0.0620 for 4935 observed reflections with I > 2σ(I). X-ray structure analysis has confirmed the existence of γ-[Mo8O26]4－ anion in the molecule. Eight MoO6 distorted octahedra share edges with short terminal Mo-O bonds from 1.691(3) to 1.749(2)A, medium bonds from 1.868(2) to 1.965(2) A And long bonds from 2.059(2) to 2.450(2) A. In the terminal site there exist two DMF ligands bound to the Mo atom through O atoms with the Mo-ODMF bond length of 2.166(3) A, affording a bond strength of 0.433. A three-dimensional network structure was formed through hydrogen bonds.     

Synthesis and Crystal Structure of [Ni(bdpm)2(OAc)]2(N3)2·5H2O (bdpm = Bis(3,5-dimethylpyrazol-1-yl)methane, OAc = CH3COO-)

A Ni(Ⅱ) complex [Ni(bdpm)2(OAc)]2(N3)2·5H2O (bdpm = bis(3,5-dimethylpyrazol-1-yl)-methane) was synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c with a = 18.630(2), b =16.6624(19), c = 19.821(2) (A), β = 90.146(2)°, V = 6152.9(12) (A)3, Z = 4, C48H8oN22Ni2O9, Mr =1226.76, Dc = 1.324 g/cm3, F(000) = 2600 andμ = 0.680 mm-1. The structure was refined to the final R = 0.0578 and wR = 0.1337 for 10848 independent reflections (Rint = 0.0311) and 6915 observed reflections (I ＞ 2σ(Ⅰ)). The complex contains two asymmetric molecules in the cell with small difference in bond distances and bond angles. Each Ni(Ⅱ) ion is bound by four nitrogen atoms of two chelating bdpm groups in a six-membered boat conformation and two oxygen atoms from one chelating bidentate acetate group to form a distorted octahedral geometry. The complex also contains azide anion outside acting as counteranion and two crystalline water molecules to link two discrete mononuclear cations though hydrogen bonds.     

Mechanochemical reactions of molybdenum and tungsten chalcohalides with (Bu4N)2[Zn(Dmit)2]. Crystal structure of (Bu4N)2[Mo3Se5.88S1.12(Dmit)3] · 1.15CH2Cl2

The mechanochemical reactions of cluster chalcohalides M₃Q₇X₄ (M = Mo, W; Q = S, Se, Te; X = Br, I) with (Bu₄N)₂[Zn(Dmit)₂] (Dmit is 1,3-dithia-2-thionedithiolate, C₃S₅ ^2?) are studied. It is shown that the reaction of Mo₃Se₇Br₄ with (Bu₄N)₂[Zn(Dmit)₂] followed by crystallization from CH₂Cl₂ results in the formation of a new compound of the composition (Bu₄N)₂[Mo₃Se_5.88S_1.12(Dmit)₃] · 1.15CH₂Cl₂ (I) characterized by IR spectroscopy, electrospray mass spectrometry, and X-ray structure analysis. Under similar conditions, W₃Q₇Br₄ and Mo₃Te₇I₄ form binuclear complexes [M₂O₂Q₂(Dmit)₂]^2? identified by electrospray mass spectrometry. Various types of nonvalent contacts Q…Q are observed in the crystal structure of compound I.     

簇合物[Et4N]2[Mo2S4(SCH2CH2S)2]的合成及晶体结构

以(NH4)2MoS4,Et4NBr,HSCH2CH2SH为原料合成了新的簇合物——[Et4N]2[Mo2S4(SCH2CH2S)2],其结构经X射线四圆衍射仪,IR。UV及元素分析确证。其晶体属单斜晶系。晶胞参数为：a=1．0304(8)nm,b=1．4158(8)sin。c=1．1417(1)nm,V=1．63801nm^3,z=4。晶体结构经块状矩阵最小二乘法修正后,最终偏离因子R=0．084。     

从固相反应产物[NEt4]4[Mo2O2S6Cu6I4Br2]合成原子簇[MoOS3Cu3I(3,5-diMePy)4]·CH3CN和(EtN)4[Mo4Cu8O4S12{(Ph2PS)2}4](英文)

Treatment of iodide-bridged dimer [NEt4] 4[Mo2O2S6Cu6I4Br2] 1 with 3, 5-bimethylpyridine or with K[(Ph2PS) 2N] in CH3CN afforded the tetranuclear cluster [MoOS3Cu3I(3,5-diMePy)4]·CH3CN 2 and dodecanuclear cluster (Et4N)4[Mo4Cu8O4S12{(Ph2PS)2N}4] 3. Monomeric 2 possess a nest-shaped skeleton.The structure of oligomeric 3 can be regarded as a tetramer of nest-shaped MoCu3OS3[(Ph2PS)aN]groups co-polymerized by sharing the limbic Cu atoms.     

Hydrothermal Synthesis and Structure of a Novel Molybdenum Phosphate: Na4(H3O) [Na(HPO4)2(PO4)4Mo18O49]·16H2O①

The title compound Na5H37P6Mo18O90 1 (Mr=1658) was synthesized under hydrothermal condition and its crystal structure was determined by X-ray diffraction. It crystallized in the monoclinic system, space group P21 with a =14.957(1), b =16.535(1), c = 16.159(1)?,β=108.586(2)°, V=3787.85?3, Dc =3.040g/cm3, Z=2,μ(MoKα)=3.17mm－1, F(000)=3242. The final R and wR are 0.0500 and 0.1535 for 6643 observable reflections with I≥2σ(I), respectively. The result of structure analysis indicates that [Na(HPO4)2(PO4)4－Mo18 O49]5－anions 2 in 1 has the symmetry of C2V, in which each MoVIO6 octahedron is connected to adjacent PO4 tetrahedra through corner-sharing and to adjacent octahedra through edge-sharing or corner-sharing.