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1.
三取代钨硅杂多配合物的导电性和磁性   总被引:5,自引:0,他引:5  
合成了α-NamHn[SiW9M3(H2O)3O37]·16H2O(M=Co(Ⅱ),Ni(Ⅱ),V(Ⅴ)杂多配合物),通过ICP,IR,UV,TG-DTA,XPS,EPR,极谱等手段进行了表征.配合物在室温下的电导率σ值达1×10-3S·cm-1,343K时可达1×10-2S·cm-1,是有实用化前景的新型固体电解质.变温磁化率结果表明α-Na10[SiW9Co3(H2O)3O37]·16H2O和α-Na10[SiW9Ni3(H2O)3O37]·16H2O具有反铁磁性.  相似文献   

2.
王富权  马荣华 《分析化学》1994,22(12):1244-1247
本文系统地研究了α和βi-K5SiM(H2O)W11O39.nH2O(略写为α,βi-SiW11M,M=Al.Ga,i=1.2.3)的氧化还原性质,提出其还原机理,讨论了杂多酸阴离子的结构对其氧化还原性质的影响。确定了极谱第1波半波电位的顺序。  相似文献   

3.
采用离子交换法将过渡金属离了三元取代钨杂多阴离子引入Zn2Al型阴离子粘土层内,得到柱撑水滑石Zn2Al(OH)6-SiW9Z3O40(Z=Ti^4+,Mo^6+)及Zn2Al(OH)6-SiW9Fe3(H2O2)3O37。ZRD及IR表明,杂多阴离子引入水滑石层间后,水滑石层内高度为1.0nm。  相似文献   

4.
取代型钨镓杂多配合物的导电性及其磁性   总被引:11,自引:1,他引:11  
合成了过渡金属取代的钨镓杂多配合物α-Na7「GaW11Co(H2O)O39」.16H2O,α-Na7H2「GaW10Co2(H2O)2O39」.16H2O和α-NanHm「GaW9ME(H2O)3O37」.16H2O「M=Co(Ⅱ),Ni(Ⅱ,)V(Ⅴ)」,通过红外,紫外,ICP,TG-DTA,EPR,XPS,^183WNMR,极谱等手段进行了表征。  相似文献   

5.
本文合成通式为(NH4)17[Ln(α2-P2W17O61)2].xH2O(Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Dy)的镧系双2:17钨磷杂多配合物纯净异构体。并用^3^1PNMR,IR,UV-Vis吸收光谱,极谱,循环伏安和磁化率等对其进行了表征。对α1,α2和β异构体间的性质进行了比较。 α2异构体的L n-O键离子特性强于α1异构体。  相似文献   

6.
庄鸿辉  吴鼎铭 《结构化学》1996,15(6):469-472
标题化合物由BiCl3和乙酰丙酮在HCl(气)/C2H5OH溶剂中通入H2S气体反应而得。晶体属四方晶系,Mt=1130.76,空间群P41212。晶胞参数a=b=8.867(2),c=41.511(4)A;V=3264(1)A^3,Z=4,Dc=2.30gcm^-3,μ(MoKa)=118.607cm^-1,F(000)=2104.晶结构由重原子法求得。最终偏离因子R=0.072。晶体由分立的(  相似文献   

7.
利用酯基锡与缺位Keggin结构杂多阴离子PW9O9-34反应,合成了6种新的杂多阴离子有机金属配合物M9[(R′OOCCHR″CH2SnOH2)3(PW9O34)2]·xH2O(M=(CH3)4N+,K+;R′=CH3_,CH3CH2_;R″=H,CH3_),通过元素分析、IR光谱、紫外电子光谱、1HNMR、31PNMP、183WNMR和TGA-DSC热分析等测试手段对标题配合物进行了表征和性质研究,确定该系列配合物为A-β-PW9型夹心配合物结构.  相似文献   

8.
通过SnCl_2对化合物Me_2Si[η~5-C_5H_4Fe(CO)]_2(μ-CO)_2(Ⅰ)中Fe-Fe键的插入反应以及Ⅰ被Na-Hg齐还原所生成的相应双铁负离子{Me_2Si[η~5-C_5H_4Fe(CO)_2]_2}~(2-)与SnR_2Cl_2(R=Me,Ph)的亲核反应,合成了环状化合物Me_2Si[η~5-C_5H_4Fe(CO)_2]_2SnR_2[R=Cl(1),Me(2),Ph(3)]。以元素分析、IR和~1HNMR谱表征了它们的结构,并用X射线衍射测定了配合物3的晶体结构。3为单斜晶系,空间群P2_1/n,a=1.0384(3)nm,b=1.6384(1)nm,c=1.5762(5)nm,β=97.93(2)°,V=2.656(2)nm~3,Z=4,Dx=1.71g/mL。  相似文献   

9.
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。  相似文献   

10.
合成了(NH4)n[LaSb9W21O86M3]·xH2O(M=Mn,Co,Ni,Cu,Zn,Cr,Fe),通过元素分析、183WNMR核磁共振谱、可见光谱、电化学测定对其进行了表征。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

17.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

18.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

19.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

20.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

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