Synthesis and Crystal Structure of Binuclear Oxomolybdenum(VI) Complex with Both o-Mercaptophenolate

The complex (Bu4N) 2 [Mo2O5 (mp)2] was synthesized by the reactionof (Bu4N)2[Mo8O26] with H2mp (H2mp=o-mercaptophenol) in methanol. The molecular formula is C44H80Mo2N2O7S2, M.=1005.10. The complex is crystallized in monoclinic, space group P21/n with unit cell parameters, a = 17. 829 (2) A, b= 13. 759 (2 )A,c= 21. 974(2) A, g=105. 386(8)°, V= 5197. 4(1) , Dc= 1. 285 g/cm3, Z=4,λ(MoKa) =0. 71073 , μ=0. 607 mm-1,F(000) = 2120, final R=0.0348 and wR=0. 0741 for 4912 independent observed reflections (FM>4σ(Fo) ). Two MoO5S units inthe complex molecule exhibits the con facial distorted bioctahedral geometry and possesses an approximate C2 symmetry.

Facile synthesis of La_2Mo_2O_9 nanoparticles via an EDTA complexing approach

A facile EDTA （ethylene diamine tetraacetic acid） complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and Fourier transform infrared spectroscopy （FT-IR）. The results show that a homogeneous transparent gel can be obtained with EDTA as the organic complexing reagent under the pH value of 3.0. Further thermal decomposition of the as-synthesized transparent gel by increasing the temperature up to 600℃ for 3 h results in the formation of La2Mo2O9 nanoparticles with a crystal size of about 30 nm. Moreover, the nanoparticles tend to form micrometer-sized aggregates with a three-dimensional network structure, which shows promising applications in solid oxide fuel cells （SOFC）, catalysts and so on.

THE STUDY OF STRUCTURE AND DYNAMICS OF DINUCLEAR COMPLEXES ［Mo（VI）］_2－EDTA AND ［Mo（VI）］_2－EGTABY^1HNMR

The 1H and 13C NMR spectra of the dinuclear complexes of molybdenum(VI) withethylenediaminetetraacetic acid ([Mo(VI)]2-EDTA) and 3,12-bis(carboxymethyl)-6.9-dioxa-3,12-diazatetra-decanedioic acid(tMo(VI)]2-EGTA) at various temperatures were measured. The solutionstructure of the two dinuclear complexes was determined and the possible exchange process of theisomers is suggested

SYNTHESIS AND REACTIVITY OF OXOPEROXOMOLYBDENUM(Ⅵ)COMPLEXES:THE ACTIVE SPECIES IN THE HALCON EPOXIDATION PROCESS

Two oxoperoxomolytxlenum(Ⅵ)complexes,MoO(O_2)(OCH_2CH_2)_2NH.H_2O(5)and MoO(O_2)(OCH(CH_3)CH_2)_2 NH(6)have been synthesized by the reaction of MoO_2(OCH_2CH_2)_2NH·CH_3OH(3)and MoO_2(OCH(CH_3)CH_2)_2NH(4)with tert-butyl hy- droperoxide,and are active to epoxidize cyclohexene.

8-羟基喹啉钼(VI)二氧配合物[MoO_2(C_9H_6NO)_2]的合成、晶体结构及热性能分析

通过X 射线单晶衍射,确定了化合物[MoO2 (C9H6NO)2 ]的晶体结构。化合物晶体属单斜晶系,空间群为C2/c,晶胞参数a=1 .341 6 ( 3 )nm,b= 0. 934 46 ( 19 )nm,c=1 .362 2(3)nm,β=109 .78(3)°,Z=4。该化合物通过Mo原子有一个二重对称轴。在[MoO2 (C9H6NO)2 ]的分子结构中, Mo(VI)原子处于扭曲的八面体中心,N(1)、N(1A)、O(2)、O(2A)位于八面体的赤道位置,O(1)、O(1A)位于八面体的顶点位置。从晶胞堆积图中可看到,通过C(8)—H(8A)…O(1)有一潜在的弱的氢键,使标题化合物的结构更稳定。

Mo(VI)-5-Br-PADAP-KBrO_3极谱吸附波研究

在0.0046mol/L HAC-0.0046mol/L NaAC(PH=4.8)溶液中,以5.39×10-4mol/L2[(5-溴-2-吡啶)-偶氮]-5-(二乙氨基)苯酚(5-Br-PADAP)与0.018mol/L KBrO3为体系,峰电位EP=-0.71V(VS.SCE),峰电流与Mo(VI)浓度在1.5×10-8mol/L-2.0×10-6mol/L范围内呈线性关系下,检出限可达5.0×10-9mol/L,并且用多种电化学手段研究极谱波的性质及反应机理,实验表明为具吸附性质的吸附波。应用该法测定污水、自来水中Mo(VI)含量及回收实验,结果表明此法简便可行。

Synthesis and CD Spectra of Chiral Molybdenum-fullerenyl Complexes with Pineno-bipyridine Ligands

The synthesis and characterization of two chiral fullerene complexes (+)_(430)^(CD)-[Mo(η~2-C_(60))(CO)_3(L^(RR))] 1 and (-)_(430)^(CD)-[Mo(η~2-C_(60))(CO)_3(L^(SS))] 2 were described. The CD spectra of 1 and 2 inthe visible range show weak Cotton effects, which are approximately of mirror image, indicatingthat the appended pineno-groups with opposite chirality in bipyridines can perturb the fullerenechromophores through the molybdenum centers and lead to induced CD effects.

Synthesis and Structure Characterization of Oxo Complex of Molybdenum(Ⅵ): MoO_2(C_9H_6NO)_2

The solid state reaction of MoCl3. 3H2O with 8--hydroxylquinine givesthe title compound MoO2, (C9H6NO)2. The crystallographic data for C18,H12,N2O4.Mo=monoclinic, space group C2/c, a= 13. 357(4), b= 9. 434(2), c= 13. 540(5) A, β=109. 39(6)°, V= 1609 (2) A3, Z= 4, M.= 416. 24, D.= 1. 72 g/cm3, μ(MoKa) 8. 19 cm-l, F(000) = 832, R= 0. 049 and Rw= 0. 058 for 1118 observed refletions.The Mo atom is,coordinated by two N atoms and two O atoms from two 8-hydroxylquinine and other two terminal O atoms, forming octahedral coordination geometry.

UV-Vis Spectrum and the Third-order Nonlinear Optical Properties of the Chiral Camphorderived β-diketonate Platinum Complexes

UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G＊ level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.

SYTHESE AND REACTIONS OF HETEROBINUCLEAR COMPLEXES [PhCl_2SnM(Cl)(CO)_3(CH_3CN)_2] (M = Mo, W)

Abstract The complexes [M（CO）;（CH;CN）;]（M=Mo, W）react with an equimolar quantity ofPhSnCl;in dichloromethane at room tempreture to afford new heterobinuclearcomplexes [PhCl;SnM（Cl）(CO);（CH;CN）;] [M=Mo（1）; W（2）]. The complexes reactwith two equivalents of PR;R’（R=Ph, R’=Ph, Me; R=Cy, R’=H） to yield stablecomplexes [PhCl;SnM（Cl）(CO);（PR;R’）;]. Reaction of[PhCl;SnM（Cl）(CO);（CH;CN）;]with one equivalent of PPh;（CH;）nPPh;（n=I,2） or bulky phosphine ligands PBu;Clin dichloromethane at room tempreture to give [PhCl;SnMo（Cl）(CO);{PPh;（CH;）n-PPh;}] .CH;Cl;, [PhCl;SnMo（Cl）(CO);PBu;Cl]. CH;Cl;, respectively. The complexes1 and 2 react with phosphite donor ligands P（OMe）;to give [PhCl;SnM（Cl）(CO);-{P（OMe）;};]. All complexes have been characterized by elemental analysis, IRand;HNMR spectroscopies. Here we report the preliminary results of this work.

THE FIRST BINUCLEAR MOLYBDENUM AND TUNGSTEN COMPLEXES WITH DOUBLY-BRIDGING PYRIDINE-2-THIOLATO LIGANDS.X-RAY CRYSTAL STRUCTURE OF THE COMPLEX[Mo_2(CO)_4(μ-pyS)_2(PPh_3)_2].2C_7H_8

The title complex was obtained by reactions of [Mo(CO)_3(MeCN)_3] with [CuBr(pySH)(PPh_3)_2]or directly with pySH and PPh_3. The latter method can be used to synthesize the corresponding tungsten complex [W_2(CO)_4(μ-pyS)_2(PPh_3)_2].The molecular structure of the title compound was determined by X-ray diffraction method.

STUDIES ON ORGANO-MOLYBDENUM AND TUNGSTEN COMPOUNDS(Ⅲ)——CATALYTIC POLYMERIZATION OF ACETYLENE BY M-O-C BOND-CONTAINING COMPLEXES OF Mo AND W

Catalytic polymerization of acetylene in the presence of n5-C5H5-M-(CO)3 R (M=Mo,W;R=CH3-,C2H5-) has been studied.The results show that these complexes possess catalytic activities for the polymerization and copolymerization of monosubstituted acetylene.The catalytic mechanism has been preliminarily discussed.It is suggested that the active species be metal-car-bene.In our previous publications we reported the synthesis of some new Fischer's molybdenum and tungsten-carbene complexes and catalytic activity for alkyne polymerization.The results show that the activity of Fischer's molybdenum-carbene is higher than that of tungsten.The catalytic polymerization of alkyne by M-σ-c bond-containing complexes of molybdenum and tungsten has not been reported yet in literature.Therefore,four M-σ-C bondontaining complexes of molybdenum and tungsten were synthesized by using the method reported in the literature,and catalyst polymerization of alkyne by these complexes was examined.

Catalytic Synthesis of Salicylate Esters over Cordierite Honeycomb Coated with Mo (VI)/ZrO₂

Solid acids such as ZrO2 & Mo (VI)/ZrO2 were coated on a honeycomb monolith by impregnation method. These catalytic materials were characterized by NH3-TPD, PXRD and SEM techniques. Salicylate esters were synthesized via transesterification of methyl salicylate with different alcohols over these catalytic materials. An excellent yield of Salicylate esters was obtained under specific reaction conditions. A correlation between the surface acidity, PXRD phase and catalytic activity of Mo (VI)/ZrO2 was observed. The thermally regenerated catalytic material was reused repeatedly with a consistent high yield of salicylate esters. The honeycomb coated with zirconia catalysts were found to be economical, efficient and ecofriendly (3E concept).

SYNTHESIS AND STRUCTURE OF A MIXED-VALENCE HEXAMOLYBDENUM COMPLEX [Et_4N]_2[Mo_6O_(19)H_4]

A hexamolybdenum complex, [Et_4N]_2[Mo_6O_(19)H_4] crystal, with pentavalent and hexavalent molybdenum has been obtained in the solution of DMF and CH_3OH as organic solvents using MoCl_5 as a starting material. The crystallographic parameters obtained by X-ray diffraction analysis are: crthorhombic, a=10. 757(3), b=10. 763(2), c=14. 238(4)A, =1648. 9A^3; Z=2; space group Pnnm; final R=0. 047; final Rw=0. 051^(**)

Synthesis and Structure of a 〔Mo_3S_7]~(3.5+) Complex〔Mo_3(μ_3-S)(μ_2-S_2)_3 (Et_2dtc)_3〕_2Cl

The title complex, was pre-pared by using (NH4)2MoS4 as a starting material. X-ray crystal structural analysis ofthe complex gave the following parameters: In this complex, weak bond-ing of Cl- to three axial sulfur atoms was found with average distance of 2. 717 TheCl atom locates at a special position and is bonded weakly by two cluster cations, indi-cating the oxidation number of + 1/2 for the cluster cation.

Studies on the Phenylfluorone-Mo(Ⅵ) Complex as Interacting Mode Spectroscopic Probe of Protein in OP Microemulsion Medium

The application of phenylfluorone (PF)-Mo(VI) complex as a spectroscopic probe is studied. In the presence of OP microemulsion at pH 3.04, PF-Mo(Ⅵ) complex combines protein rapidly to form a stable compound and the absorbance at 527 nm is in proportion to the concentration of protein in the range 0-16 μg mL-1 for bovine serum albumin (BSA). OP microemuslion media is introduced into protein determination, it has increased markedly the sensitivity of the system. The molar absorption coefficient was 5.98×l06 L mol-1 cm-1 for BSA. The assay, with sensitivity, simplicity and tolerance to many foreign substances, is applied to the determination of protein in samples with satisfactory results. Moreover, the binding number of BSA with the complex, which is determined by molar ratio and slope ratio methods, is in good agreement.

Electronic structure & yield strength prediction for dislocation-Mo complex in the γ phase of nickel-based superalloys

Molybenum＇s effects when added in the γ phase of nickel-based superalloys were studied using the lattice Green＇s function multiscale method. The electronic structure of the dislocation-Mo complex was analyzed and hybridization was found to contribute to the strengthening. Moreover, by combining the interaction energies calculated from two scales, the yield stress was theoretically predicted at 0 K and finite temperature.

基于氮氧自由基配体的锰和钴双核配合物的分子结构和磁性

合成了2个基于氮氧自由基配体且结构类似的双核配位化合物,其分子式分别为[Mn_(2)(hfac)_(4)(NIT-mo-pmy)_(2)](1)和[Co_(2)(hfac)_(4)(NIT-mo-pmy)_(2)](2),其中hfac=六氟乙酰丙酮,NIT-mo-pmy=2-(2-甲氧基-5’-嘧啶基)-4,4,5,5-四甲基咪唑啉基-3-氧-1-氧自由基。2个配合物均属于三斜晶系P1空间群,其双核配位单元进一步构筑为中心对称的平行四边形分子阵列。变温磁化率的测试表明,在2个配合物中,中心离子和氮氧自由基单元之间存在反铁磁交换作用。借助构效关系研究,分析了磁作用强度的差异。通过适当近似的磁化学模型,对Mn(Ⅱ)配合物的磁性行为进行了定量拟合,并与相关化合物磁作用强度进行了比对、分析。

花岗质复式岩体成因及其与W-Mo成矿的关系——以广西油麻坡岩体为例

广西陆川米场-博白三滩成矿带是近几年新发现的以W、Mo矿化为主的多金属成矿带。本文对带内与W-Mo矿床有关的油麻坡复式岩体进行了锆石U-Pb年代学、岩石学、地球化学和Sm-Nd同位素研究。油麻坡岩体由花岗闪长岩(主体)和白云母花岗岩(补体)两部分组成。传统观点一般认为补体是主体经历分离结晶后的残余岩浆,而本文LA-ICP-MS锆石U-Pb定年结果表明,主体和补体分别形成于109.0±0.3Ma和100.7±0.5Ma,后者明显晚于前者约10Ma,说明两者不大可能是同一岩浆房演化的产物。来自岩石学、地球化学和同位素方面的证据也不支持两者是分离结晶关系,主要包括:①主体含自形角闪石,常见榍石和磁铁矿等副矿物,表明岩浆富水、高氧逸度的性质。而补体不含角闪石,常见萤石、钛铁矿和硫化物等副矿物,表明岩浆富F和偏还原的性质。这与两者的分离结晶演化关系不吻合;②补体锆石的U含量极高(平均高达10602×10-6),从而出现特有的蜕晶现象、裂纹等放射性损伤结构,明显不同于主体锆石(平均U含量为860×10-6);③补体强烈亏损Sr、Ba、Eu和LREE,富集Na、Rb、Ga以及W、Sn等成矿元素,并具有典型的稀土四分组效应和non-CHARAC特征,微量元素模拟计算表明,补体与主体没有演化关系;④主体和补体的Nd同位素组成差别较大(εNd(t)分别为-5.1^-4.0和-9.6^-8.6)。本文提出高度演化的补体花岗岩是新的幔源岩浆底侵导致下地壳部分熔融而形成,由于其富F,导致岩浆固相线大幅下降(岩浆期延长),所以经历了比主体岩浆更为强烈的熔-流体相互作用,有利于萃取W、Mo等金属元素并使之富集成矿。