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1.
Stephen Costin 《Tetrahedron letters》2009,50(8):922-925
Novel amino-dithiaphospholane complexes of ruthenium, iridium, and rhodium were synthesized, and their properties were studied. Reaction of the new amino-dithiaphospholane (RS)2 (R = binaphthyl, R′ = CH2Ph, (rac)-4) with [RuCl2(p-cymene)]2 afforded [RuCl2(p-cymene)((rac)-4)] in 67% isolated yield. Similarly, the new amino-dithiaphospholanes (RS)2 (R = cyclohexyl, (rac)-7) and (RS)2 (R = phenyl, 9) gave upon reaction with [RhCl(CO)2]2 and [IrCp∗Cl2]2 the novel complexes [RhCl(CO)(L)2] and [IrCp∗Cl2(L)] (L = (rac)-7, 9) in 61-96% yields. The ruthenium complex is catalytically active for the etherification of propargylic alcohols with methanol and ethanol (8-48 h, 90 °C, 40-85% isolated yields). 相似文献
2.
A procedure for the determination of ruthenium in iron meteorites involves its oxidation to RuO4 by sodium periodate in hydrochloric acid and extraction of the tetroxide into chloroform. Various parameters of the method were studied: sample dissolution, optimum amount of oxidant, shaking time, distribution ratio and stability of the complex. The relative standard deviation assessed from replicate analyses of the North Chile iron meteorite was 6.6%. There are no certified standards for iron meteorites, but the value of 20.0 μg g? obtained for this meteorite compares well with a reported abundance of 19.3 μg g?1 obtained by radiometric neutron-activation analysis (RNAA). The analysis of 15 meteorites that had previously been analysed by RNAA gave values averaging 11% below those reported by the latter method, but within the standard deviation of the RNAA data. It is considered that the present method is a more practical alternative to RNAA for the determination of ruthenium in iron meteorites. 相似文献
3.
Flow-injection preconcentration and graphite furnace atomic absorption spectrometric determination of platinum 总被引:1,自引:0,他引:1
Flow-injection graphite furnace atomic absorption spectrometric (GFAAS) methods were worked out using oxime, sulphoxine and 2,2′-diamino-diethylamine (DEN) cellulose microcolumns for preconcentration of platinum after reduction by iodide or sulphite ions. The detection limits were, at 20-fold enrichment, 0.21, 0.18 and 0.30 μg l−1, respectively. The total reflection X-ray fluorescence spectrometry (TXRF) was also used for the determination of platinum in eluates. The method was applied for the determination of platinum in salmeterol xinafoate and Ca-folinate pharmaceutical compounds. Decomposition of organic matrix of Ca-folinate was necessary before the preconcentration. 相似文献
4.
Padavattan Govindaswamy Georg Süss-Fink Ji?í Ludvík 《Journal of organometallic chemistry》2007,692(8):1661-1671
The mononuclear complexes [(η5-C5Me5)IrCl(L1)] (1), [(η5-C5Me5)RhCl(L1)] (2), [(η6-p-PriC6H4Me)RuCl(L1)] (3) and [(η6-C6Me6)RuCl(L1)] (4) have been synthesised from pyrazine-2-carboxylic acid (HL1) and the corresponding complexes [{(η5-C5Me5)IrCl2}2], [{(η5-C5Me5)RhCl2}2], [{(η6-p-PriC6H4Me)RuCl2}2], and [{(η6-C6Me6)RuCl2}2], respectively. The related dinuclear complexes [{(η5-C5Me5)IrCl}2(μ-L2)] (5), [{(η5-C5Me5)RhCl}2(μ-L2)] (6), [{(η6-p-PriC6H4Me)RuCl}2(μ-L2)] (7) and [{(η6-C6Me6)RuCl}2(μ-L2)] (8) have been obtained in a similar manner from pyrazine-2,5-dicarboxylic acid (H2L2). Compounds isomeric to the latter series, [{(η5-C5Me5)IrCl}2(μ-L3)] (9), [{(η5-C5Me5)RhCl}2(μ-L3)] (10), [{(p-PriC6H4Me)RuCl}2(μ-L3)] (11) and [{(η6-C6Me6)RuCl}2(μ-L3)] (12), have been prepared by using pyrazine-2,3-dicarboxylic acid (H2L3) instead of H2L2. The molecular structures of 2 and 3, determined by X-ray diffraction analysis, show the pyrazine-2-carboxylato moiety to act as an N,O-chelating ligand, while the structure analyses of 5-7, confirm that the pyrazine-2,5-dicarboxylato unit bridges two metal centres. The electrochemical behaviour of selected representatives has been studied by voltammetric techniques. 相似文献
5.
Murat Aydemir Nermin Meric Bahattin Gümgüm Ertan ?ahin 《Journal of organometallic chemistry》2011,696(13):2584-2588
Reaction of Ph2PNHCH2-C4H3S with [Ru(η6-p-cymene)(μ-Cl)Cl]2, [Ru(η6-benzene)(μ-Cl)Cl]2, [Rh(μ-Cl)(cod)]2 and [Ir(η5-C5Me5)(μ-Cl)Cl]2 yields complexes [Ru(Ph2PNHCH2-C4H3S)(η6-p-cymene)Cl2], 1, [Ru(Ph2PNHCH2-C4H3S)(η6-benzene)Cl2], 2, [Rh(Ph2PNHCH2-C4H3S)(cod)Cl], 3 and [Ir(Ph2PNHCH2-C4H3S)(η5-C5Me5)Cl2], 4, respectively. All complexes were isolated from the reaction solution and fully characterized by analytical and spectroscopic methods. The structure of [Ru(Ph2PNHCH2-C4H3S)(η6-benzene)Cl2], 2 was also determined by single crystal X-ray diffraction. 1-4 are suitable precursors forming highly active catalyst in the transfer hydrogenation of a variety of simple ketones. Notably, the catalysts obtained by using the ruthenium complexes [Ru(Ph2PNHCH2-C4H3S)(η6-p-cymene)Cl2], 1 and [Ru(Ph2PNHCH2-C4H3S)(η6-benzene)Cl2], 2 are much more active in the transfer hydrogenation converting the carbonyls to the corresponding alcohols in 98-99% yields (TOF ≤ 200 h−1) in comparison to analogous rhodium and iridium complexes. 相似文献
6.
Yasuhiro Yamamoto Hideki Nakamura Jian-Fang Ma 《Journal of organometallic chemistry》2001,640(1-2):10-20
Reactions of [(η6-arene)RuCl2]2 (1) (η6-arene=p-cymene (1a), 1,3,5-Me3C6H3 (1b), 1,2,3-Me3C6H3 (1c) 1,2,3,4-Me4C6H2(1d), 1,2,3,5-Me4C6H2 (1e) and C6Me6 (1f)) or [Cp*MCl2]2 (M=Rh (2), Ir (3); Cp*=C5Me5) with 4-isocyanoazobenzene (RNC) and 4,4′-diisocyanoazobenzene (CN–R–NC) gave mononuclear and dinuclear complexes, [(η6-arene)Ru(CNC6H4N=NC6H5)Cl2] (4a–f), [Cp*M(CNC6H4N=NC6H5)Cl2] (5: M=Rh; 6: M=Ir), [{(η6-arene)RuCl2}2{μ-CNC6H4N=NC6H4NC}] (8a–f) and [(Cp*MCl2)2(μ-CNC6H4N=NC6H4NC)}] (9: M=Rh; 10: M=Ir), respectively. It was confirmed by X-ray analyses of 4a and 5 that these complexes have trans-forms for the ---N=N--- moieties. Reaction of [Cp*Rh(dppf)(MeCN)](PF6)2 (dppf=1,1′-bis (diphenylphosphino)ferrocene) with 4-isocyanoazobenzene gave [Cp*Rh(dppf)(CNC6H4N=NC6H5)](PF6)2 (7), confirmed by X-ray analysis. Complex 8b reacted with Ag(CF3SO3), giving a rectangular tetranuclear complex 11b, [{(η6-1,3,5-Me3C6H3)Ru(μ-Cl}4(μ-CNC6H4N=NC6H4NC)2](CF3SO3)4 bridged by four Cl atoms and two μ-diisocyanoazobenzene ligands. Photochemical reactions of the ruthenium complexes (4 and 8) led to the decomposition of the complexes, whereas those of 5, 7, 9 and 10 underwent a trans-to-cis isomerization. In the electrochemical reactions the reductive waves about −1.50 V for 4 and −1.44 V for 8 are due to the reduction of azo group, [---N=N---]→[---N=N---]2−. The irreversible oxidative waves at ca. 0.87 V for the 4 and at ca. 0.85 V for 8 came from the oxidation of Ru(II)→Ru(III). 相似文献
7.
A simple accurate and precise analytical method for the determination of platinum, ruthenium, and molybdenum in Pt, PtRu, and PtMo nanoparticles catalysts deposited on high-surface area carbon by flame atomic absorption spectrometry (FAAS) and graphite furnace atomic absorption spectrometry (GFAAS) is described. The complete digestion of samples (0.010-0.020 g), which contain noble metals (NMs) in the range between 0 and 30% in combination among them or with other non-NMs, is obtained under mild conditions using both concentrated HCl and HCl+HNO3 (1+1 (v/v)) mixture to boiling for 30 min in an open vessel. Carbon is separated from the solution by filtering it. Under optimized conditions of the flame, the poor sensitivity of platinum is enhanced 50-fold in presence of 1% (m V−1) ascorbic acid, whereas the analytical signal of ruthenium increased by the presence of co-existing platinum. Any kind of interference is observed on the analytical signal of molybdenum. Recovery test obtained by analyzing commercial powder catalysts ranged from 99 to 101%. The precision, expressed as relative standard deviation of five measurements, is better than 1%. Electrode catalysts, made by using the carbon-supported platinum-based powder catalysts, have been analyzed for the metal loadings onto the electrode by GFAAS after dissolution under the same conditions used for the powder catalysts. The precision, expressed as relative standard deviation of three measurements, is better than 2%. 相似文献
8.
Copper and zinc (0.01–1 μg g?1)in high-purity bismuth are extracted together as their thiocyanate complexes into methyl isobutyl ketone and determined by atomic absorption spectrometry with a tungsten-strip atomizer. The concentrations of copper found by the proposed method agree well with the values obtained by similar atomic absorption spectrometric methods involving prior extraction of copper as its bathocuproine or diethyldithiocarbamate complex. 相似文献
9.
Column preconcentration and electrothermal atomic absorption spectrometric determination of rhodium in some food and standard samples
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Mohammad Ali Taher Fatemeh Pourmohammad Hamid Fazelirad 《Journal of separation science》2015,38(23):4153-4158
In the present work, an electrothermal atomic absorption spectrometric method has been developed for the determination of ultra‐trace amounts of rhodium after adsorption of its 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol/tetraphenylborate ion associated complex at the surface of alumina. Several factors affecting the extraction efficiency such as the pH, type of eluent, sample and eluent flow rates, sorption capacity of alumina and sample volume were investigated and optimized. The relative standard deviation for eight measurements of 0.1 ng/mL of rhodium was ±6.3%. In this method, the detection limit was 0.003 ng/mL in the original solution. The sorption capacity of alumina and the linear range for Rh(III) were evaluated as 0.8 mg/g and 0.015–0.45 ng/mL in the original solution, respectively. The proposed method was successfully applied for the extraction and determination of rhodium content in some food and standard samples with high recovery values. 相似文献
10.
Maria Bertília Oss Giacomelli Jos Bento Borba da Silva Tatiana Dillenburg Saint'Pierre Adilson Jos Curtius 《Microchemical Journal》2004,77(2):151-156
The most severe interferences in atomic absorption spectrometry are caused by the presence of anions when they are in different concentrations in the samples and in the calibration solutions. The analyte addition technique or matrix matching calibration can be employed to minimize or compensate the non-spectral interferences, but they are time consuming or difficult to be carried out. The use of chemical modifiers usually allows higher pyrolysis temperatures and consequently the removal of components of the sample matrix, equalizing the analyte signal in the sample and in the calibration solution. In this work, a mixture of Ir and Rh is proposed as permanent modifier to determine As, Cd and Pb in diluted hydrochloric, sulfuric and phosphoric acids and in ethanol and methanol by electrothermal atomic absorption spectrometry (ET AAS) with calibration against 1% v/v nitric acid aqueous solutions. The performance of the proposed permanent modifier was compared to that of Pd plus Mg nitrates in solution. Better recoveries, low background levels and faster analysis were obtained with the permanent modifier. The permanent modifier was also successfully employed for the determination of As, Cd and Pb in different concentrations of sulfuric and hydrochloric acids. For the phosphoric acid, the proposed modifier was only efficient for acid concentrations up to 2% v/v for As and up to 5% v/v for Cd and Pb. The precision, expressed as the relative standard deviation (n=3), was lower than 10%, for all samples, including ethanol and methanol. 相似文献
11.
The dinuclear dichloro complexes [(η6-arene)2Ru2(μ-Cl)2Cl2] and [(η5-C5Me5)2M2(μ-Cl)2Cl2] react with 2-(pyridine-2-yl)thiazole (pyTz) to afford the cationic complexes [(η6-arene)Ru(pyTz)Cl]+ (arene = C6H61, p-iPrC6H4Me 2 or C6Me63) and [(η5-C5Me5)M(pyTz)Cl]+ (M = Rh 4 or Ir 5), isolated as the chloride salts. The reaction of 2 and 3 with SnCl2 leads to the dinuclear heterometallic trichlorostannyl derivatives [(η6-p-iPrC6H4Me)Ru(pyTz)(SnCl3)]+ (6) and [(η6-C6Me6)Ru(pyTz)(SnCl3)]+ (7), respectively, also isolated as the chloride salts. The molecular structures of 4, 5 and 7 have been established by single-crystal X-ray structure analyses of the corresponding hexafluorophosphate salts. The in vitro anticancer activities of the metal complexes on human ovarian cancer cell lines A2780 and A2780cisR (cisplatin-resistant), as well as their interactions with plasmid DNA and the model protein ubiquitin, have been investigated. 相似文献
12.
The extraction of rhodium and iridium with 4-(non-5-yl)pyridine (NP) was investigated. The rate of rhodium extraction increases with increasing concentration of NP and chloride ions. Spectroscopic studies indicate that the extracted species is an ion pair, RhCl3?6 3HNP+. Under the conditions of optimum Rh extraction ([Cl?]=3.7 M, [NP]=0.3 M, [H]=0.08 M), iridium is also extracted by NP with similar efficiency in the form of IrCl3?6 3HNP+. The use of hypophosphorous acid to labilize rhodium results in a better extraction of rhodium without significantly changing the extraction of iridium. The efficiency and kinetics of the rhodium extraction improve with increasing chloride concentration. For [Cl?] ? 3.7 M, [H3PO2]=2.5 M, [NP]=0.3 M and Ph ≈ 1.6, 82% of rhodium is extracted in 4 min and 95% in 30 min. 相似文献
13.
14.
A series of neutral pyridine-based organochalcogen ligands, 2,6-bis(1-methylimidazole-2-thione)pyridine (Bmtp), 2,6-bis(1-isopropylimidazole-2-thione)pyridine (Bptp), and 2,6-bis(1-tert-butylimidazole-2-thione)pyridine (Bbtp) have been synthesized and characterized. Reactions of [Cp*M(μ-Cl)Cl]2 (Cp* = η5-pentamethylcyclopentadienyl, M = Ir, Rh) with three pyridine-based organochalcogen ligands result in the formation of the complexes Cp*M(L)Cl2 (M = Ir, L = Bmtp, 1a·Cl2; M = Rh, L = Bmtp, 1b·Cl2; M = Ir, L = Bptp, 2a·Cl2; M = Rh, L = Bptp, 2b·Cl2; M = Ir, L = Bbtp, 3a·Cl2; M = Rh, L = Bbtp, 3b·Cl2), respectively. All compounds have been characterized by elemental analysis, NMR and IR spectra. The molecular structures of Bbtp, 1a·Cl2, 1b·Cl2, 2b·Cl2 and 3b·Cl2 have been determined by X-ray crystallography. 相似文献
15.
16.
Chang Xijun Li Yanfeng Luo Xingyin Zhan Guangyao Su Zhixing Gao Jencheng 《Analytica chimica acta》1991
Poly(vinyldiethylenetriamine) chelating resin was synthesized from macroporous poly(vinyl chloride) and used for the enrichment-separation of rhodium and iridium. The efficiency, rate and equilibrium constant adsorption of rhodium and iridium on the resin were determined and real samples were analysed. The mechanism of rhodium and iridium enrichment is discussed. 相似文献
17.
强酸性条件下 ,钯 (Ⅱ )与 5 [( 5 氯 2 吡啶 )偶氮 ] 2 ,4 二氨基甲苯 ( 5 Cl PADAT)生成紫红色螯合物 ,该螯合物可与十二烷基苯磺酸钠 (SDBS)生成离子缔合物 ,离子缔合物经 0 .3μm孔径的硝化纤维微孔滤膜富集后 ,于小体积 ( 0 .5mL)的浓硫酸中溶膜 ,用石墨炉原子吸收法 (GFAAS)测定 ,富集倍数可达 2 0 0倍 ,钯含量在 4.69× 1 0 - 1 2 ~ 7.0 9× 1 0 - 9mol/L范围内线性良好 ,检出限为 1 .78×1 0 - 1 2 mol/L。方法用于海水中痕量钯的测定。 相似文献
18.
A sensitive and reliable ETAAS determination of metal traces in high purity silver after total (Bi, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb) and partial (As, Hg, Sb, Se) separation of the matrix with ascorbic acid is described. The temperature program is optimized for analyte determination in ascorbic acid media and in 1% silver solution. 相似文献
19.
Platinum, iridium and rhodium in mixtures are determined sequentially, with rubeanic acid, tin(II) chloride and tin(II) iodide respectively. The working ranges (in microg) are: Pt 7-100, Rh 7-70, Ir 7-30. 相似文献
20.
A sensitive and reliable ETAAS determination of metal traces in high purity silver after total (Bi, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb) and partial (As, Hg, Sb, Se) separation of the matrix with ascorbic acid is described. The temperature program is optimized for analyte determination in ascorbic acid media and in 1% silver solution. 相似文献