具有β2-Keggin结构主族元素钨砷杂多配合物的合成与性质

合成了4种主族元素取代的钨砷杂多配合物,通过ICP和TG曲线确定其通式为:K11,12〔M(AsW11O39)2〕.xH2O和K3,4[AsZ(OH2)W11O39].xH2O(M=Pb2 ,Bi3 ;Z=Sn4 ,Sb3 ).采用IR,UV,XRD,XPS,183W NMR等方法证明其结构为β2-Keg-gin结构,用极谱和循环伏安法研究了配合物的氧化还原性和热稳定性,结果表明:所合成的配合物只有一步双电子还原过程,电位较高,表现出强氧化性;配合物将在550℃~600℃范围内分解.     

过渡金属取代的钨铝杂多配合物的制备、表征和性质

用分步设计法合成了以铝为中心原子的过渡元素与钨的三元杂多配合物,经ICP、TG分析确定其化学式为K_4，6，7[AlM(OH₂)W₁₁O₃₉]·xH₂O(M=V⁵⁺、Cr³⁺、Mn²⁺、Fe³⁺、Co²⁺、Ni²⁺、Cu²⁺、Zn²⁺、Cd²⁺)。采用IR、UV、XRD、¹⁸³W和²⁷Al NMR等对配合物的结构进行了表征,表明配合物具有Keggin结构；循环伏安法对该系列配合物的氧化还原性质研究表明,其氧化还原过程为不可逆的两电子还原,配合物的磁化率测试均表现为顺磁性,还对其热稳定性进行了讨论。     

含2A主族元素杂多钨酸盐的合成及性质

本文报道了K_nZXW_(11)O_(39)·xH_2O和K_nZ’(XW_(11)O_(39))_2·xH_2O(X=B,Si,As;Z=Mg,Ca;Z’=Sr,Ba)两个系列,12种含2A主族元素杂多配合物的合成,并通过元素分析,离子交换实验、电导滴定、IR、UV、XRD和TG-DTA等方法,对配合物进行了表征,比较了它们的热稳定性。     

镧系元素钨钒杂多配合物的合成与表征

报道了镧系元素钨钒杂多配合物的合成方法。元素分析和热重分析确定其通式为：Ｋ７Ｈ６「Ｌｎ（ＶＷ１０ＶＯ３９）２」．ｘＨ２Ｏ（Ｌｎ＝Ｌａ＾３＋、Ｃｅ＾３＋、Ｐｒ＾３＋、Ｎｄ＾３＋、Ｓｍ＾３＋、Ｅｕ＾３＋、Ｇｄ＾３＋、ｄＹ＾３＋、Ｙｂ＾３＋）。利用红外，喇曼，电子自旋共振，紫外和Ｘ射线衍射谱对其进行了表征。配合物的热解性质研究表明，其分解温度范围为４００－４５０℃，还研究了的氧化还原性质。     

碱土金属钨铬杂多配合物的合成、表征及热稳定性研究

用直接法合成了以Cr为中心原子的碱土金属和W的三元杂多配合物,经ICP和TG曲线确定其化学式为K7[CrA(H2O)W11O39].xH2O(A=Mg2 ,Ca2 ,Sr2 和Ba2 ),采用IR,UV,XRD,XPS和183W NMR等手段对配合物结构进行了表征,确认所合成的配合物为-αKeggin结构.借助TG-DTA详细讨论了配合物的热稳定性,得出合成配合物的热稳定温度为450℃左右.     

镧系元素钨硅杂多配合物异构体的合成及性质

合成了通式为K_(13)[Ln(β_i-SiW_(11)O_(39))_2]·xH_2O(Ln=La,Ce,Pr,Nd,Sm,Gd,Er;β_i=β_1,β_3)的两个系列的β-异构体。通过元素分析、极谱、循环伏安法,UV和VIS光谱、磁化率以及热分析等手段研究了异构体的组成和性质。     

三甘氨酸双11钨硅双核稀土杂多配合物的合成与性质

利用一缺位杂多酸对一维链式配合物的断链取代反应,合成了未见文献报道的以甘氨酸为桥联配体的双核稀土杂多配合物,其结构简式为K₁₀[(O₃₉W₁₁Si)RE(Gly)₃RE(SiW₁₁O₃₉)]·9H₂O(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Y;Gly=NH₃⁺CH₂COO<     

铝镓取代的钨硅杂多配合物位置异构体的合成表征及催化性能

合成了通式为Ｋ５－ｎＨｎ［α－，βｉ－ＳｉＷ１１Ｍ（Ｈ２Ｏ）Ｏ３９］·ｘＨ２Ｏ（Ｍ＝Ａｌ，Ｇａ，βｉ＝β１，β２，β３）的八种异构体。通过元素分析、红外光谱和紫外光谱、极谱和循环伏安、２７Ａｌ和１８３Ｗ核磁共振、Ｘ光电子能谱等方法进行了表征。所合成的各异构体在催化以Ｈ２Ｏ２为氧化剂的顺丁烯二酸环氧化反应中，β３异构体具有最高的催化活性     

希土元素钼钨硅多元杂多配合物的合成、结构和性质研究

本文报道了标题系列配合物K_(10)H_3[Ln(SiMo_(11-n)W_nO_(39))_2]·mH_2O(n=2、4;Ln=La~(3+)、Ce~(3+)、Pr~(3+)、Nd~(3+)、Sm~(3+)、Eu~(3+)、Gd~(3+)、Dy~(3+)、Yb~(3+))的合成、热解性质、氧化还原性以及某些波谱特性。测定了K_(10)H_3[La(SiMo_9W_2O_(39)_2]·27H_2O的单晶结构:a=17.224(6)(?),b=26.952(11)(?),c=21.158(7)(?),β=103.76(3)°,Z=4,V=9540.17(6)(?)~3,F(000)=8663,此晶体属于单斜晶系,P2_1/n空间群。     

稀土元素11－钨锌合铝杂多配合物的合成、表征和催化性能

首次合成出稀土元素１１一钨锌合铝杂多配合物，用元素分析、红外光谱、紫外光谱、Ｘ射线光电子能谱和热分析等对合成产物进行了表征。其分子通式为：ＬｎＨ４［Ａｌ（Ｈ２Ｏ）ＺｎＷ１１Ｏ３９］·ｘＨ２Ｏ（Ｌｎ＝Ｌａ，Ｐｒ，Ｎｄ，Ｓｍ）。在此基础上，对其在合成己二酸二（２－乙基己）酯（ＤＯＡ）中的催化性能进行了研究。结果表明，稀土元素１１－钨锌合铝杂多配合物具有较高的催化活性和选择性，且可以重复使用。ＤＯＡ产品质量高，达到食品包装级。     

锰为中心原子的三元杂多配合物的合成与氧化还原性质研究

用直接法合成了以锰为中心原子的过渡元素和钨的三元杂多配合物,经ICP和TG曲线确定其化学式为K5,6[MnM(OH2)W11O39]·xH2O(M=Mn2+,Fe3+,Co2+,Ni2+,Cu2+,Zn2+和Cd2+),采用IR,UV,XRD和XPS等手段对配合物结构进行了表征,用循环伏安测定了其系列配合物的氧化还原性质,得出系列配合物的氧化性顺序,同时讨论配合物的热稳定性.     

Synthesis and properties of mesogenic laterally fluorinated compounds containing benzoxazole unit

Series of mesogenic laterally fluorinated compounds, 2-(2′,3′-difluoro-4′-alkoxybiphenyl-4-yl)-benzoxazole derivatives (nB-Fx) bearing different substituents (H, CH₃, Cl, NO₂, coded as nB-FH, nB-FM, nB-FC and nB-FN, respectively) at 5-position, were prepared and characterised. Their phase transition behaviour was investigated by differential scanning calorimetry and polarising optical microscopy. nB-Fx with alkoxy chain lengths of 2 to 10 carbons exhibited enantiotropic mesophases, for which the mesophase ranges were 0°C–58°C and 0°C–71°C on heating and cooling for nB-FH, 41°C–93°C and 66°C–140°C for nB-FM, 44°C–133°C and 87°C–155°C for nB-FC, and 0°C–76°C and 0°C–95°C for nB-FN, respectively. Compared to non-fluorinated analogues, with the exception of nB-FC, fluorinated nB-Fx mainly exhibited nematic mesophase both in heating and cooling, which were attributed to the disruption of the side-to-side intermolecular packing caused by the two ortho-lateral fluoro substituents. For nB-Fx series, nB-FM, nB-FC and nB-FN exhibited a much wider mesophase range than the corresponding nB-FH series, which indicated that the substituent at benzoxazole moiety was helpful in increasing the mesophase stability. With the exception of nB-FN, the nB-Fx series displayed intense photoluminescence emission at 379–383 nm in methylene chloride solution, when it was excited at its absorption maxima.     

An alternative way of characterising the bonding in compounds featuring main-group elements and with the potential for multiple bonding: on the dissociation of binary main-group hydrides

Herein the bonding in compounds featuring main-group elements and with the potential for multiple bonding is studied theoretically by examination of their fragmentation into two fragments that still exhibit the same structure as they had in the molecule prior to dissociation. The fragments were calculated both in their electronic ground state and in an excited electronic state, in which the number of unpaired electrons is equal to the maximal number of bonds in the compounds before dissociation. The energies of the fragmentation processes (DeltaE(frag)) can be more directly linked to the bond strengths than the dissociation energies (DeltaE(diss)), because of the absence of any secondary effects like relaxation of the electronic state or of the geometry of the fragments. These relaxation energies of the fragments (DeltaE(frag)) are also studied herein. The energies derived in this work allow for an accurate comparison of the bonding properties in main-group-element hydrides. The trends of the fragmentation and relaxation energies are discussed in detail. It will be shown that the relaxation energies allow for a classification of the bonds ("classical" sigma and pi bonds or donor-acceptor interactions), while the fragmentation energies are good quantitative measures for the total bond strength. Similar calculations are on the way to explore the bonding in systems in which the hydrogen atoms are replaced by organic groups or halogen atoms.     

十一钨锆杂多配合物位置异构体的合成表征及催化性能

过渡元素取代的杂多配合物由于其独特的催化活性和抗病毒性受到人们的重视 ,由于缺位 β位的介稳定性和异构化 ,给合成带来了一定的困难。我们发现 ,某些单取代金属衍生物中 β异构体具有良好的催化活性[1 ,2 ] 。本文报道了通式为α ,βi K6[SiW1 1 ZrO40 ]·XH2 O( βi=β1 ,β2 ,β3)的四种异构体 (简记作α ,β SiW1 1 Zr)的合成、表征及四种异构体对烯烃环氧化反应的催化活性 ,为研究Zr杂多化合物的应用提供选择。1　实验部分1 1　仪器与试剂日本岛津IR 40 8红外光谱仪 (KBr压片 ) ,美国PE公司产λ 35型紫外分光光谱仪 ;384B…     

Synthesis,characterization, and thermal properties of silicon(IV) compounds containing amidinate ligands as CVD precursors

The title compounds of the type R-C(=NⁱPr) (-N′ ⁱPrSiMe₃) (with R = Me or ⁿBu) as potential chemical vapor deposition (CVD) precursors have been synthesized and characterized by ¹H, ¹³C, and ²⁹Si NMR spectroscopy as well as by EI-MS and elemental analysis where necessary. Thermal properties, including stability, volatility, transport behavior, and vapor pressure, were evaluated by thermogravimetric analysis to confirm that they are suitable for the CVD procedure. Deposition was accomplished in a hot wall CVD reactor system, which qualitatively verified the ability of these compounds as CVD precursors.     

Synthesis and study the liquid crystalline properties of compounds containing benzoxazole core and terminal vinyl group

Terminal vinyl-based benzoxazole liquid crystalline compounds, 2-(3-fluoro-4?-alkoxy-1,1?-biphenyl ?4-yl)-5-(2-propenyloxymethyl)-benzoxazole (nPPF(2)BP), were synthesised and their structures were confirmed by infrared (IR) spectra, proton nuclear magnetic resonance (¹H-NMR) spectra, gas chromatography with electron impact-mass spectrometry (GC/EI-MS), matrix-assisted laser desorption/ionisation-time of flight (MALDI-TOF) mass spectrometry and elemental analysis (EA). The compounds show enantiotropic smectic/nematic phases with mesophase ranges are 71–97 °C and 87–136°C on heating and cooling processes for nPPF(2)BP, respectively. They give low melting points due to lateral fluoro substituent and flexible terminal 2-propenyloxymethyl chain. It is found that the compounds nPPF(2)BP with shorter alkoxy chain (n = 3, 4) exhibit a wide range of nematic mesophase, which is ascribed to enhanced π–π interaction caused by terminal vinyl moiety, whereas further elongation of the terminal alkoxy chain results in supressing nematic phase and increasing smectic mesophase. Compared with methyl terminated analogues, 2-propenyloxymethyl terminated compounds nPPF(2)BP display much lower melting points and wider or comparable mesophase range both in heating and cooling.     

柱水滑石（Ⅰ）ZnAl-La(TiW11)2的合成、表征及其催化性能

柱水滑石（Ⅰ）ZnAl-La(TiW11)2的合成、表征及其催化性能;稀土杂多配离子;柱撑水滑石;合成;表征;催化性能     

新型二茂铁三氮唑类Schiff碱的合成、晶体结构及其电化学性质

以乙酰二茂铁和氨基三氮唑为原料,合成了两种新型的二茂铁三氮唑Sch iff碱化合物,其结构通过IR,1H-NMR,元素分析和X-射线单晶衍射法确定。X射线单晶结构分析表明,固态时化合物1 a与一分子水通过分子间氢键形成-维无限链状结构,其晶体属单斜晶系,P21/n空间群,M r:312.16,a=11.679(2),b=9.862(2),c=12.717(3),β=108.60(3)0k,v=1388.3(5),Z=4,D c=1.493mg.m-3,μ=0.71073,F(000)=648,最终偏离因子R=0.0454,wR=0.0984。电化学分析表明1 a和1b的电化学性质相似,在电位0.4~1.1V范围内,都只有一对氧化-还原峰,对应于Fc/Fc 电对,且该过程是受扩散控制的可逆过程。     

Synthesis,structure, and magnetism of four polyoxomolybdate compounds containing yttrium and ytterbium

Four new polyoxometalate compounds consisting of Anderson-type anions and trivalent rare earth (RE) cations, [RE ₂ (H₂O)₁₄M(OH)₆Mo₆O₁₈][M(OH)₆Mo₆O₁₈]?·?14H₂O, RE?=?Y, M?=?Cr(1), Al(2); RE?=?Yb, M?=?Al(3), Cr(4), have been synthesized in aqueous solution and characterized by elemental analyses, infrared (IR) spectra, thermal gravimetric (TG) analyses, and single crystal X-ray diffraction. [M(OH)₆Mo₆O₁₈]^3? as a bidentate ligand coordinates to two RE ^{3 +} , forming a double-supported cation [RE ₂(H₂O)₁₄M(OH)₆Mo₆O₁₈]³⁺. The cations and other [M(OH)₆Mo₆O₁₈]^3? anions in the crystals are linked via hydrogen bonding interactions tightly, forming four supramolecular compounds. The magnetic properties of 1, 3, and 4 have been examined by measuring their magnetic susceptibilities from 2 to 300?K.     

Synthesis,characterization, optical,thermal and electrical properties of polybenzimidazoles

The variation of dielectric constant and dielectric loss of two novel polybenzimidazole (PBI) were studied at constant temperature with variable frequency. The polymers have shown maximum dielectric constant at low applied frequency 50 Hz at 393 K due to the space charge polarization. The AC conductivity and activation energy of polymers were arrived from dielectric constant and dielectric loss values. PBIs were synthesized by the oxidative polycondensation of benzimidazole monomers, 2-(1H-benzo [d] imidazole-2-yl)-4-bromophenol (BIBP), and 2-(1H-benzo [d] imidazole-2-yl)-6-methoxyphenol (BIMP) in an aqueous alkaline medium using NaOCl as oxidant. The monomers and polymers were characterized by various spectroscopic techniques. Fluorescence spectra of monomers and polymers showed their λ _max emission in the region of 472–479 and 463–472 nm respectively. The electrical conductivities of iodine doped polybenzimidazoles were measured by four-point probe technique and it increases with increase in iodine vapour contact time. The electrical conductivity values were correlated with the charge density on imidazole nitrogen obtained from Huckel calculation method. Both the PBI are having reasonably good thermal stability and are shown by high carbines residues of around 40% at 500°C in thermogravimetric analysis.