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1.
《Analytical letters》2012,45(5-6):503-528
Abstract

Ruthenium(III) forms a 1:2 complex with allyl thiourea. Conformity to Beer's law was observed for up to 12 pg/ml of ruthenium, in acidic medium.

The molar absorptivity of the complex is 1.66E+04 1 mol?1 cm?1, at 270 nm; the Sandell's sensitivity of the reaction for ruthenium is 0.0061 μg cm?2 per 0.001 absorbance unit.

The tolerance to diverse ions is quite satisfactory.

The infrared spectra of allyl thiourea and of its ruthenium complex, recorded in the 2.5 - 50 μ region, reveal that only sulphur-to-ruthenium bonds are present in the complex.

A comparison with the main, most recent, spectrophotometric reagents for ruthenium is reported. The present method has the advantages of simplicity and reasonable sensitivity.  相似文献   

2.
《Analytical letters》2012,45(19):2453-2466
Abstract

A sensitive method for the simultaneous determination of osmium(VIII) and Palladium(II) (up to 15 μ9/ml of Os and 11 μ9/ml of Pd) in mixtures, by first and second derivative spectrophotometry, using allyl thiourea as reagent, is described.

A statistical analysis of the results is reported.  相似文献   

3.
The title compound, Pd[(NH2)2CS]4Cl2, has been synthesized and structurally characterized. It crystallizes in orthorhombic, Pna2(1) space group , with Mr=481.79(C4H16Cl2N8PdS4), a=12.943(3), b=8.283(2), c=15.148(3)?, V=1623.9(6)?3Z=4. The Pd(Ⅱ) ion has an square-planar geometry, and is coordinated by four S atom donors from four thiourea molecules. The two Cl- anions found in the apical position balance the charge. In the solid state, the title compound forms three dimensional network structures through hydrogen bonds. The inter-molecular hydrogen bonds connect the {Pd[(NH2)2CS]4}2+ and chloride ion to contribute to the stability of the structure. CCDC: 193379.  相似文献   

4.
本文报道了极易溶于水的显色剂N-烯丙基-N'-(氨基对苯磺酸钠)硫脲(ASATu)光度法测定钯(Ⅱ)的条件:在pH4.0~5.5缓冲介质中,ASATu与钯生成易溶于水的、稳定的黄色络合物,组成比为:Pd(Ⅱ):ASATu=1:4;络合物的最大吸收波长为296.0nm,表观摩尔吸光系数ε_(296)=1.33×10~5L·mol~(-1)·cm~(-1);钯(Ⅱ)在0~20μg/25 mL呈线性,相关系数γ=0.9995.该法灵敏度高、选择性好、操作简便,用于阳极泥和矿石中钯的测定,结果满意.  相似文献   

5.
6.
Allylic acetates were reduced with Pd(0)-SmI2 in the presence of ArSeBr to form corresponding allylic selenides in good yields.  相似文献   

7.
8.
《Analytical letters》2012,45(11):1905-1916
Abstract

A method is proposed for the simultaneous determination of mercury(II) and palladium(II) by first-derivative spectrophotometry based on the absorption spectra of their complexes with 5-(3,4-Methoxyhydroxyphenylmethylene)-2-thioxo-1,3-thiazolidine [5-(3,4-methoxyhydroxybenzylidene) rhodanine]. Zero-crossing measurement technique is found suitable for the measurement of the first-derivative value at the specified wavelengths. Mercury(II) (0.4-1.4 μg ml?1) and palladium(II) (0.08 - 1.8 μg ml?1) in different ratios have been determined simultaneously. A critical evaluation of the proposed method is performed by statistical analysis of the experimental data.  相似文献   

9.
IntroductionIsonitrosoketonesandrelatedligandssuchasni trosophenolesareusedasanalyticalreagents .1Complexesofcobaltmetals2 ,3withisonitrosoketoneiminesarerelevanttothechemistryandbiochemistryofthevitaminB12 coen zymes .Isonitroso(oximino)groupofthoseligandsc…  相似文献   

10.
Three palladium (II) complexes with the isonitrosobenzoylacetoneimine (HIBI) ligand, Pd (p‐CH3C6H4IBI)2 (1), Pd (C6H5IBI)2 (2) and Pd2Cl2 (C6H5CH2IBI)2 · CHCl3 (3), were prepared and characterized by IR, Raman and X‐ray diffraction studies. The geometries around the palladium atoms in the complexes 1 and 2 are distorted trans‐PdN4 square planes, and the Schiff base ligands RIBI? are coordinated through their oximo‐nitrogen atoms and imino‐nitrogen atoms. The week Pd…H? C agostic interactions [Pd…H = 0.2764 nm] complete the hexacoordinate environment around palladium in the complex 1. The octahedral deformation of the classical square planar environment of the Pd atom is due to the week Pd…O (1b) interactions [Pd? O (1b) = 0.3157 (9) nm] in the complex 2. The complex 3 is a first example of binuclear complex with isonitrosoketoimine ligands, in which one of oximo groups is coordinated through oximo‐nitrogen and oximo‐oxygen atoms.  相似文献   

11.
Palladium ate complexes are frequently invoked as important intermediates in Heck and cross‐coupling reactions, but so far have largely eluded characterization at the molecular level. Here, we use electrospray‐ionization mass spectrometry, electrical conductivity measurements, and NMR spectroscopy to show that the electron‐poor catalyst [L3Pd] (L=tris[3,5‐bis(trifluoromethyl)phenyl]phosphine) readily reacts with Br ions to afford the anionic, zero‐valent ate complex [L3PdBr]. In contrast, more‐electron‐rich Pd catalysts display lower tendencies toward the formation of ate complexes. Combining [L3Pd] with LiI and an aryl iodide substrate (ArI) results in the observation of the PdII ate complex [L2Pd(Ar)I2].  相似文献   

12.
CrystalandMolecularStructureofDi-chloro-bis(р-methylphenylbutylsulfide)Palladium(Ⅱ)¥GuoSong-Shan;CuiLi;WangHang-Zhang;QianPu(...  相似文献   

13.
1 INTRODUCTIONRecently,thiosemicarbazoneshaveattractedmuchattentionwithinbiologicalsystemandcoordinationchemistry.[1-3]IthasbeenpostulatedthatmanyNheterocycliccarbaldehydethiosemicarbazonesactastridentateN2Sligandswhichbondtoironorcopperinthesynthesisofp…  相似文献   

14.
The crystal and molecular structure of [Ag2(ETU)6]·(ClO4)2 has been determined by X-ray crystallography. It crystallizes in the monoclinic, space group P21/c, with lattice parameters a=0.63270(9)nm, b=2.4264(2)nm, c=1.2128(1)nm, β=92.721(9)°, V=1.8597(3)nm3, Z=4, Dc=1.835Mg·m-3, F(000)=1032, μ=1.591mm-1. The molecule is built up of centro-symmetric dimeric entities, in which the four-membered Ag2S2 ring is planar and the angle of S(3)-Ag(1)-S(3A) is 107.70(2)° for symmetry requirements. The silver atoms have slightly distorted tetrahedral coordination environment, and the sulfur atoms of the ETU group occupy four coordi-nation sites. The two percholate anions in general position balance the charge. In the solid state, the title compound forms three dimensional network structures through hydrogen bonds. The intermolecular hydrogen bonds and ex-tensive intermolecular interaction connect the [Ag2(ETU)6]2+ ion and two ClO4- anions to contribute to the stability of the structure. CCDC: 208731.  相似文献   

15.
合成了三元配合物 [Pd(biqu) (mal) ]·H2 O (biqu为 2 ,2′ 联喹啉 ,mal2 -为丙二酸根 ) .测定了配合物对肺腺癌细胞AGZY 83a的抑制活性 ,IC50 值为 2 1 9μg/mL .用荧光光谱、紫外光谱和圆二色谱测定了配合物与鱼精DNA的作用规律 .求出配合物与DNA的键合常数KM 为 2 0 3× 10 8.测定了配合物与pBR3 2 2质粒DNA作用的凝胶电泳图谱 .多种实验结果表明 ,配合物主要以插入方式与DNA发生键合作用 .  相似文献   

16.
The standard molar enthalpies of formation of crystalline dialkyldithiocarbamates chelates, [Pd(S2CNR2)2], with R=C2H5, n-C3H7, n-C4H9 and i-C4H9, were determined through reaction-solution calorimetry in acetone, at 298.15 K. From the standard molar enthalpies of formation of the gaseous chelates, the homolytic (172.4±3.8, 182.5±3.2,150.9±3.1 and 162.6±3.1 kJ mol−1) and heterolytic (745.0±3.8, 803.7±3.3,834.3±3.1 and 735.2±3.0 kJ mol−1) mean palladium-sulphur bond-dissociation enthalpies were calculated. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Three palladium(II) complexes with amino-amidato-phenolato-type tridentate ligands were synthesized and characterized by 1H NMR spectroscopy and X-ray crystallography. The strategic arrangement of a hydrogen-bond donor and acceptor adjacent to the substitution site of the PdII complex allowed the selective coordination of nucleosides. Among two pyrimidine-nucleosides, cytidine and 5-methyluridine, cytidine was successfully coordinated to the PdII complex while 5-methyluridne was not. On the other hand, both purine-nucleosides, adenosine and guanosine, were coordinated to the PdII complex. As purines have several coordination sites, adenosine afforded three kinds of coordination isomers expected from the three different donors. However, guanosine afforded a sole product according to the ligand design such that the formation of double intramolecular hydrogen-bond strongly induced the specific coordination by N1-position of guanine moiety. Furthermore, the preference of the nucleosides was evaluated by scrambling reactions. It was found that the preference of guanosine is nearly twice as high as adenosine and cytidine, owing to the three-point interaction of a coordination bond and two hydrogen bonds. These results show that the combination of a coordination and hydrogen bonds, which is reminiscent of the Watson–Crick base pairing, is an effective tool for the precise recognition of nucleosides.  相似文献   

18.
有机金属钯硅碳烷树状分子液晶配合物研究   总被引:7,自引:2,他引:7  
树状分子具有规整结构,其分子体积、形状和功能基团可在分子水平上控制,金属有机树状分子及其超分子化学倍受关注[1].含锌、铁、钴、镍、铂、钌或铑的金属有机树状配合物的研究已有报道[2,3],但有机金属钯树状配合物则未见报道.传统的液晶分子为刚性棒状,按...  相似文献   

19.
The last decade has witnessed the rapid development of high-valent Pd-involved organic transformations. This has also led to a steadily growing number of publications concerning the preparation of isolable and characterizable palladium(III) and palladium(IV) complexes. A variety of one-electron and two-electron oxidants have been employed to give access to high-oxidation-state Pd compounds. Undoubtedly, the study of these stoichiometric reactions has great implications for relevant Pd-mediated catalysis. In this minireview, the focus is on the synthetic approaches to structurally determined PdIII/IV complexes starting from their PdII precursors, and the advances in this research area from early 2010 to late 2019 will be highlighted. Chemical oxidations exploiting various oxidizing agents including 1) hypervalent iodine reagents; 2) halogens; 3) electrophilic fluorination reagents; 4) alkyl/aryl halides; 5) ferrocenium salts; 6) peroxides/O2; 7) sulfonyl chlorides; and 8) others are covered. A “greener” electrooxidation manner has also been reviewed.  相似文献   

20.
Abstract

Four different series of N,N-dimethylaminoalkylchalcogenolates, viz. Me2NCH2 CH2E?, Me2NCH(Me)CH2E?, Me2NCH2CH(Me)E?, and Me2NCH2CH2CH2E? (E = S, Se, Te), (referred as EN) have been synthesized and characterized. Their reactions with palladium(II) and platinum(II) precursors have been explored. Complexes of the general formula, [MCl(EN)]n, [MCl(EN)2]n, [MCl(EN)(PR3)], [M2Cl2(μ-EN)2(PR3)2], [M2(μ-EN)2(PP)2]2+, etc. have been isolated. All the complexes have been characterized by elemental analysis, IR, NMR (1H, 13C, 31P, 77Se, 125Te, 195Pt), UV-vis, and FAB mass spectral data. A weak absorption in the electronic spectra of [MCl(EN)(PR3)] has been attributed to metal mediated ligand-to-ligand charge transfer and showed pronounced chalcogen dependence being red shifted on moving from S → Se → Te. Structures of several complexes have been established by X-ray diffraction analyses. Thermal behavior of some of these complexes has been investigated by TGA.  相似文献   

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