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1.
本文用电化学方法研究了铌和过氧铌一、三取代Dwson结构杂多配合物:a2-MaHbP2W15NbO62.xH2O,a-1,2,3-MaHbP2W15Nb3O62.xH2O,a2-MaHbP2W17(NbO2)O61.xH2O,a-1,2,3-MaHbP2W15(NbO2)3O59.xH2O(M=K,TMA,TEA和TBA)共十六种盐的氧化还原性质。  相似文献   

2.
钼钨的杂多化合物(HPC)在催化、电催化、分子材料、药物等诸多领域中已显示出独特的功能。含过氧金属离子取代的杂多阴离子在催化以过氧化氢为氧化剂的烯烃环氧化反应中具有很高的活性和选择性。近年来,含铌的杂多配合物由于良好的催化活性和抗病毒性,引起了人们的重视。本文合成了8种Keggin结构过氧铌钨磷杂多配合物,并用红外、紫外吸收光谱、极谱-循环伏安、及^183W NMR谱等测试手段对其结构和性质进行了确定和比较,考察了它们对烯烃环氧化反应的催化活性。  相似文献   

3.
Dawson结构钨铌磷杂多配合物~(183)WNMR谱的研究龚剑,瞿伦玉,陈亚光,李宝利(东北师范大学化学系,长春130024)张建国(中国科学院长春应用化学研究所,长春130022)关键词:Dawson结构杂多配合物,钨铌磷杂多配合物,~(183)W...  相似文献   

4.
5.
本文首次合成了11种镧系元素Dawson结构钨磷杂多配合物:Ln_2[P_2W_(18)O_(62)]·xH_2O(Ln=La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Yb),对它们进行了红外光谱、紫外光谱、极谱、X射线粉末衍射和X光电子能谱研究,并对其结构进行了讨论。  相似文献   

6.
近年来,有机多金属氧酸盐电荷转移配合物由于有特殊的光、电、磁性质在催化、功能材料及药物化学等领域受到研究者的广泛关注[1]。自从1988年法国的L.Ouahab[2]首次报道(TTF)6PW12O40(Et4N)2的合成以来,已见报道的多金属氧酸盐仅限于AndersonEvanse、lindquist和Keggin结构的多阴离子,对它们功能性质的系统研究也未见文献报道。为了研究阴离子的大小和形状对标题化合物功能性质的影响,作者在以前工作的基础上[3,4],首次以Dawson结构杂多钨磷(砷)…  相似文献   

7.
本文报导了用卡宾的钨配合物进一步用于与二氯甲基Wittig试剂的反应, 合成1,1-二氯-2-烷氧基烯烃。1,1-二卤代烯烃是一类产生不饱和卡宾的前体化合物。本文旨在通过对卡宾的钨配合物与二氯代Wittig试剂之间的反应研究, 进一步研究烷氧基取代不饱和卡宾的性质。  相似文献   

8.
综述了近年来在新型多硫1,2-二硫醇烯配合物的合成,结构和性质方面的研究进展以及这些配合物作为分子导体,超导体,磁性材料和光电功能材料的应用前景。  相似文献   

9.
氢基钨配合物;烷氧基钨配合物的合成及β-H消去反应  相似文献   

10.
β┐二羰基化合物的电解氧化偶联反应朱洪友张成敏刘复初*(云南大学化学系昆明650091)关键词β-二羰基化合物,电氧化,偶联反应1997-06-04收稿,1997-12-10修回云南省应用基础研究基金资助项目在有机合成上,β-二羰基化合物的偶联是形成...  相似文献   

11.
In a high‐yield one‐pot synthesis, the reactions of [Cp*M(η5‐P5)] (M=Fe ( 1 ), Ru ( 2 )) with I2 resulted in the selective formation of [Cp*MP6I6]+ salts ( 3 , 4 ). The products comprise unprecedented all‐cis tripodal triphosphino‐cyclotriphosphine ligands. The iodination of [Cp*Fe(η5‐As5)] ( 6 ) gave, in addition to [Fe(CH3CN)6]2+ salts of the rare [As6I8]2? (in 7 ) and [As4I14]2? (in 8 ) anions, the first di‐cationic Fe‐As triple decker complex [(Cp*Fe)2(μ,η5:5‐As5)][As6I8] ( 9 ). In contrast, the iodination of [Cp*Ru(η5‐As5)] ( 10 ) did not result in the full cleavage of the M?As bonds. Instead, a number of dinuclear complexes were obtained: [(Cp*Ru)2(μ,η5:5‐As5)][As6I8]0.5 ( 11 ) represents the first Ru‐As5 triple decker complex, thus completing the series of monocationic complexes [(CpRM)2(μ,η5:5‐E5)]+ (M=Fe, Ru; E=P, As). [(Cp*Ru)2As8I6] ( 12 ) crystallizes as a racemic mixture of both enantiomers, while [(Cp*Ru)2As4I4] ( 13 ) crystallizes as a symmetric and an asymmetric isomer and features a unique tetramer of {AsI} arsinidene units as a middle deck.  相似文献   

12.
合成并表征了新的Co(salen)化合物(2a~2c3a~3c)。手性Co(salen)化合物2a~2c在硫醚的不对称氧化反应中显示了中等的反应活性,但只获得了较低对映选择性(8%~21% ee),而手性Co(salen)化合物3a~3c在该反应中没有反应活性。通过研究整个配体的构象影响对化合物的低对映选择性进行了讨论。  相似文献   

13.
The use of [Cp′′2Zr(η1:1-E4)] (E=P ( 1 a ), As ( 1 b ), Cp′′=1,3-di-tert-butyl-cyclopentadienyl) as phosphorus or arsenic source, respectively, gives access to novel stable polypnictogen transition metal complexes at ambient temperatures. The reaction of 1 a/1 b with [CpRNiBr]2 (CpR=CpBn (1,2,3,4,5-pentabenzyl-cyclopentadienyl), Cp′′′ (1,2,4-tri-tert-butyl-cyclopentadienyl)) was studied, to yield novel complexes depending on steric effects and stoichiometric ratios. Besides the transfer of the complete En unit, a degradation as well as aggregation can be observed. Thus, the prismane derivatives [(Cp′′′Ni)2(μ,η3:3-E4)] ( 2 a (E=P); 2 b (E=As)) or the arsenic containing cubane [(Cp′′′Ni)33-As)(As4)] ( 5 ) are formed. Furthermore, the bromine bridged cubanes of the type [(CpRNi)3{Ni(μ-Br)}(μ3-E)4]2 (CpR=Cp′′′: 6 a (E=P), 6 b (E=As), CpR=CpBn: 8 a (E=P), 8 b (E=As)) can be isolated. Here, a stepwise transfer of En units is possible, with a cyclo-E42− ligand being introduced and unprecedented triple-decker compounds of the type [{(CpRNi)3Ni(μ3-E)4}2(μ,η4:4-E′4)] (CpR=CpBn, Cp′′′; E/E′=P, As) are obtained.  相似文献   

14.
The coordination properties of new types of bidentate phosphane and arsane ligands with a narrow bite angle are reported. The reactions of [{Cp′′′Fe(CO)2}2(μ,η1:1‐P4)] ( 1 a ) with the copper salt [Cu(CH3CN)4][BF4] leads, depending on the stoichiometry, to the formation of the spiro compound [{{Cp′′′Fe(CO)2}231:1:1:1‐P4)}2Cu]+[BF4]? ( 2 ) or the monoadduct [{Cp′′′Fe(CO)2}231:1:2‐P4){Cu(MeCN)}]+[BF4]? ( 3 ). Similarly, the arsane ligand [{Cp′′′Fe(CO)2}2(μ,η1:1‐As4)] ( 1 b ) reacts with [Cu(CH3CN)4][BF4] to give [{{Cp′′′Fe(CO)2}231:1:1:1‐As4)}2Cu]+[BF4]? ( 5 ). Protonation of 1 a occurs at the “wing tip” phosphorus atoms, which is in line with the results of DFT calculations. The compounds are characterized by spectroscopic methods (heteronuclear NMR spectroscopy and IR spectrometry) and by single‐crystal X‐ray diffraction studies.  相似文献   

15.
Catalytic property of a series of manganese(III) complexes with tetradentate phenol‐ and pyridinebased ligands on the oxidation of the C‐H bond of diphenylmethane in the presence of hydrogen peroxide as an oxidant at ambient conditions were investigated. In this process, diphenylmethane was oxidized to the corresponding keton and alcohol. The catalytic selectivity of the complexes was evaluated.  相似文献   

16.
17.
As mimetic oxygen carrier or oxidation catalyst, Schiff base cobalt complexes such as Co (II) salen have been widely studied1-4. However their high-price greatly limited their application. The synthesis of cheap furaldehyde Schiff bases and their complexes with Co (II), as well as the dioxygen affinity and biomimetic catalytic oxidation performance of these complexes are worth trying to study. In this paper, the saturated dioxygen uptake of cobalt complexes with different bis-(furaldehyd…  相似文献   

18.
Four new Schiff base functionalized 1,2,3-triazolylidene nickel complexes, [Ni-(L1NHC)2](PF6)2; 3, [Ni-(L2NHC)2](PF6)2; 4, [Ni-(L3NHC)](PF6)2; 7 and [Ni-(L4NHC)](PF6)2; 8, (where L1NHC = (E)-3-methyl-1-propyl-4-(2-(((2-(pyridin-2-yl)ethyl)imino)methyl)phenyl)-1H-1,2,3-triazol-3-ium hexafluorophosphate(V), 1, L2NHC = (E)-3-methyl-4-(2-((phenethylimino)methyl)phenyl)-1-propyl-1H-1,2,3-triazol-3-ium hexafluorophosphate(V), 2, L3NHC = 4,4′-(((1E)-(ethane-1,2-diylbis(azanylylidene))bis(methanylylidene))bis(2,1-phenylene))bis(3-methyl-1-propyl-1H-1,2,3-triazol-3-ium) hexafluorophosphate(V), 5, and L4NHC = 4,4′-(((1E)-(butane-1,4-diylbis(azanylylidene))bis(methanylylidene))bis(2,1-phenylene))bis(3-methyl-1-propyl-1H-1,2,3-triazol-3-ium) hexafluorophosphate(V), 6), were synthesised and characterised by a variety of spectroscopic methods. Square planar geometry was proposed for all the nickel complexes. The catalytic potential of the complexes was explored in the oxidation of styrene to benzaldehyde, using hydrogen peroxide as a green oxidant in the presence of acetonitrile at 80 °C. All complexes showed good catalytic activity with high selectivity to benzaldehyde. Complex 3 gave a conversion of 88% and a selectivity of 70% to benzaldehyde in 6 h. However, complexes 4 and 7–8 gave lower conversions of 48–74% but with higher (up to 90%) selectivity to benzaldehyde. Results from kinetics studies determined the activation energy for the catalytic oxidation reaction as 65 ± 3 kJ/mol, first order in catalyst and fractional order in the oxidant. Results from UV-visible and CV studies of the catalytic activity of the Ni-triazolylidene complexes on styrene oxidation did not indicate any clear possibility of generation of a Ni(II) to Ni(III) catalytic cycle.  相似文献   

19.
Several sterically protected, low-coordinate organophosphorus compounds with P=P, P=C, and C≡P bond are described in this study. Molecules such as diphosphenes, phosphaalkenes, 1-phosphaallenes, 1,3-diphosphaallenes, 3,4-diphosphinidenecyclobutenes, and phosphaalkynes are stabilized with an extremely bulky 2,4,6-tri-t-butylphenyl (Mes*) group. The synthesis, structures, physical, and chemical properties of these molecules are discussed, together with some successful applications in catalytic organic reactions.  相似文献   

20.
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