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1.
A sensitive, simple method for the determination of trace amounts of samarium by spectrophotometry is described based on the formation of the samarium-chrome azurol S (CAS) complex in micellar medium. The molar absorptivities of the complexes at pH 7.5 at 505 nm were 3.6x10(4) and 1.4x10(5) l mol(-1) cm(-1) for water media and cetylpyridinium chloride (CPC), respectively. Beer's law is obeyed from 0.05-2 mg l(-1) of samarium at 505 nm as Sm-CAS-CPC complex. Optimal conditions such as reagent amounts, and pH for the samarium determination were reported. The effects of foreign ions were also investigated. The proposed method was successfully applied to the determination of samarium contents in synthetic samples. 相似文献
2.
Introduction8 Hydroxyquinolineisaclassicalchelatingagentfortransitionmetalsandlanthanides .Recentlymetalcom plexesincorporating 8 quinolinolatoligandshavereceivedmoreandmoreattention .Theresearchinterestprobablyarisesfromtwoaspects .First,8 quinolinolatomet… 相似文献
3.
A new reduction procedure for the stereoselective reduction of certain beta-alkoxy ketones is described. The method relies upon electron-transfer reduction using samarium diiodide in THF with MeOH as an additive. Reduction is facile for a number of alkoxy groups that can complex samarium effectively but is not observed with TBS or benzyl protecting groups. Experiments with deuterated methanol show that the stereoselectivity arises from protonation of a samarium carbanion intermediate. 相似文献
4.
A. M. Makarevich P. R. Abdyushev N. M. Sorokina I. E. Korsakov N. P. Kuz’mina 《Russian Journal of Coordination Chemistry》2006,32(10):707-711
A reaction of samarium oxide, nickel oxocarbonate, and diethylenetriaminepentaacetic acid (H5DTPA) taken in stoichiometric proportions in water gave SmNiDTPA · 10H2O as a glassy solid. The formation of this heterometallic complex was confirmed by data from elemental analysis, IR spectroscopy, thermal analysis, and X-ray fluorescence analysis. An aqueous solution of the complex was used to deposit SmNiO3 films onto a single-crystal SrTiO3(001) substrate. The SmNiO3 phase in films obtained upon 3-h annealing at 500°C was identified by powder X-ray diffraction. Films deposited from a solution of an equimolar mixture of monometallic samarium and nickel diethylenetriaminepentaacetates contained no samarium nickelate. 相似文献
5.
Dubé T Conoci S Gambarotta S Yap GP Vasapollo G 《Angewandte Chemie (International ed. in English)》1999,38(24):3657-3659
The cooperative attack of four (dipyrromethanyl)Sm(II) units on dinitrogen resulted in a novel tetranuclear samarium dinitrogen complex (shown schematically). The presence of halogen atoms inhibited reactivity with dinitrogen through the assembly of divalent samarium clusters. dipyrr=diphenylmethyldipyrrolide dianion. 相似文献
6.
《Analytical letters》2012,45(5):901-920
Abstract A sensitive and selective method is described for the determination of traces of samarium by third order derivative molecular absorption spectrophotometry (TDMAS). The method is based on the formation of a stable, blue coloured water soluble ternary complex (Metal-Chromogenic reagent-surfactant) which is formed when cetyl trimethyl ammonium bromide or cetyl pyridinium bromide is added to binary samarium-methyl thymol blue system. The influence of various instrumental parameters and reaction conditions for maximum colour development is investigated. The ternary complex detection limit is 7.5 μg of samarium present in 25 ml of final solution. Linear calibration graphs are obtained for 0–30 μg of samarium. The relative standard deviation of the procedure was calculated to be 1.6%. Gd, Tb, Dy, Ho, Tm and Lu do not interfere in TDMAS determination of samarium. Methods are described for masking other interfering analytes. 相似文献
7.
Pan CL Chen W Su S Pan YS Wang J 《Dalton transactions (Cambridge, England : 2003)》2011,40(31):7941-7945
A polynuclear samarium imido complex [(L)Sm(4)(μ(3)-NSiMe(3))(4)] (2) featuring a cubane-like cluster has been synthesized from the reaction of an organic azide and a samarium(II) complex [(L)SmI(2)Li(2)(THF)(Et(2)O)(2)] (1). In addition, this divalent samarium starting material (1) reacts with azobenzene to give the first example of a well-defined doubly-fused cubic imido-cluster [(L)Sm(6)(μ(3)-NPh)(4)(μ(4)-NPh)(2)I(2)(THF)(2)] (4) in addition to a major cubic complex [(L)Sm(4)(μ(3)-NPh)(4)] (3). 相似文献
8.
The electrochemical and spectrophotometric characterization of the complex formed from samarium diiodide and 4 equiv of tripyrrolidinophosphoric acid triamide (TPPA) is presented. Kinetic studies indicate that the SmI(2)/TPPA complex possesses reactivity greater than the complex formed between samarium diiodide and 4 equiv of HMPA. Examples of the use of SmI(2)/TPPA in synthesis are presented. 相似文献
9.
A method is described for the determination of 5-25 mug of samarium in about 40 mg of lead chloride, based on the removal of the lead by electrolysis and determination of the samarium by extraction with PAN and measurement of the extinction of the complex at 552 nm. 相似文献
10.
K Sahloul L Sun A Requet Y Chahine M Mellah 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(36):11205-11209
An electrochemical method to prepare solutions of samarium diiodide in THF is reported. The simple electrolysis of a samarium rod provides a rapid and straightforward in situ synthesis of SmI(2) . The electrogenerated complex catalyzes various C?C bond formations. The reagent is produced continuously and leads to efficient organic electrosynthesis with significantly smaller amounts of solvent than usually required. 相似文献
11.
YanCAI MingQingCHEN JuanXU PinFangWU AkashiMITSURU XiaoHuaHUAN 《中国化学快报》2004,15(9):1109-1112
Poly (N-vinylacetamide) (PNVA) was synthesized by the free radical polymerization and its samarium (Ⅲ) binary complex was prepared and characterized by means of IR, UV-vis, X-ray photoelectron spectroscopy (XPS) and fluorescence spectra. The fluorescent intensity of samarium (Ⅲ) characteristic emission was increased significantly due to efficient energy transfer from polymeric ligand to Sm (Ⅲ) ion in the complex. 相似文献
12.
The gamma-deprotonation of a samarium(III) bis(trimethylsilyl)amide complex derived from a dimetallated trans-dioxaporphyrinogen has been achieved through stabilisation of the counter cation within the macrocyclic cavity. 相似文献
13.
Yuyuan Xiao Xiao-Kun Zhao Tianpin Wu Jeffrey T. Miller Han-Shi Hu Jun Li Wenliang Huang Paula L. Diaconescu 《Chemical science》2021,12(1):227
Inverse-sandwich samarium and ytterbium biphenyl complexes were synthesized by the reduction of their trivalent halide precursors with potassium graphite in the presence of biphenyl. While the samarium complex had a similar structure as previously reported rare earth metal biphenyl complexes, with the two samarium ions bound to the same phenyl ring, the ytterbium counterpart adopted a different structure, with the two ytterbium ions bound to different phenyl rings. Upon the addition of crown ether to encapsulate the potassium ions, the inverse-sandwich samarium biphenyl structure remained intact; however, the ytterbium biphenyl structure fell apart with the concomitant formation of a divalent ytterbium crown ether complex and potassium biphenylide. Spectroscopic and computational studies were performed to gain insight into the electronic structures and bonding interactions of these samarium and ytterbium biphenyl complexes. While the ytterbium ions were found to be divalent with a 4f14 electron configuration and form a primarily ionic bonding interaction with biphenyl dianion, the samarium ions were in the trivalent state with a 4f5 electron configuration and mainly utilized the 5d orbitals to form a δ-type bonding interaction with the π* orbitals of the biphenyl tetraanion, showing covalent character.Inverse-sandwich samarium and ytterbium biphenyl complexes were synthesized and characterized by X-ray crystallography. Combined experimental and computational studies indicated that they have distinct electronic structures and bonding interactions. 相似文献
14.
Shirvani-Arani S Ahmadi SJ Bahrami-Samani A Ghannadi-Maragheh M 《Analytica chimica acta》2008,623(1):82-88
A batch process was developed to separate samarium ions from some lanthanide ions by a novel solid phase which was prepared via the ion-imprinting technique. The samarium (III) ion-imprinted polymer (IIP) particles were synthesized by preparing the ternary complex of samarium ions with 5,7-dichloroquinoline-8-ol (DCQ) and 4-vinylpyridine (VP). Then, thermally copolymerization with styrene (functional monomer, STY) and divinylbenzene (cross-linking monomer, DVB) followed in the presence of 2-methoxy ethanol (porogen) and 2,2′-azobisisobutyronitrile (initiator, AIBN). The imprinted ion was removed by stirring the above particles with 50% (v/v) HCl to obtain the leached IIP particles. Moreover, control polymer (CP) particles were similarly prepared without the samarium ions. The unleached and leached IIP particles were characterized by X-ray diffraction (XRD), infra-red spectroscopy (IR), thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM). Finally, preconcentration and selectivity studies for samarium and the other lanthanide ions were carried out. The preconcentration of the samarium (III) traces was studied during rebinding with the leached IIP particles as a function of pH, the weight of the polymer material, the preconcentration and the elution times, the eluent volume and the aqueous phase volume. These studies indicated that the samarium (III) amount as low as 1 μg, present in 200 mL, could be preconcentrated into 25 mL of 1.0 M HCl. 相似文献
15.
钐试剂在有机合成中应用的若干新进展 总被引:1,自引:0,他引:1
综述了本课题组最近几年关于钐试剂在有机合成中应用的研究进展. 主要包括以下几部分内容: (1) 二碘化钐促进的有机反应研究; (2) 金属钐直接应用于有机合成的研究; (3) 其它钐试剂 (三碘化钐, 烯丙基溴化钐) 促进的有机反应研究. 相似文献
16.
Synthesis and Structure of Unprecedented Samarium Complex with Bulky Bis‐iminopyrrolyl Ligand via Intramolecular C=N Bond Activation
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Suman Das Srinivas Anga Adimulam Harinath Hari Pada Nayek Tarun K. Panda 《无机化学与普通化学杂志》2017,643(24):2144-2148
An unprecedentate samarium complex of the molecular composition [{κ3‐{(Ph2CH)N=CH}2C4H2N)}{κ3‐{(Ph2CHN=CH)(Ph2CHNCH)C4H2N}Sm}2] ( 2 ), which was isolated by the reaction of a potassium salt of 2,5‐bis{N‐(diphenylmethyl)‐iminomethyl}pyrrolyl ligand [K(THF)2{(Ph2CH)N=CH}2C4H2N)] ( 1 ) with anhydrous samarium diiodide in THF at 60 °C through the in situ reduction of imine bond is presented. The homoleptic samarium complex [[κ3‐{(Ph2CH)–N=CH}2C4H2N)]3Sm] ( 3 ) can also be obtained from the reaction of compound 1 with anhydrous samarium triiodide (SmI3) in THF at 60 °C. The molecular structures of complexes 2 and 3 were established by single‐crystal X‐ray diffraction analysis. The molecular structure of complex 2 reveals the formation of a C–C bond in the 2,5‐bis{N‐(diphenylmethyl)iminomethyl}pyrrole ligand moiety (Ph2Py–). However, complex 3 is a homoleptic samarium complex of three bis‐iminopyrrolyl ligands. In complex 2 , the samarium ion adopts an octahedral arrangement, whereas in complex 3 , a distorted three face‐centered trigonal prismatic mode of nine coordination is observed around the metal ion. 相似文献
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18.
Efficient application of time discrimination has succeeded in substantial reduction of the detection limit of laser fluorimetry. A nitrogen laser and a pulse-gated photon counting method are combined. The detection limits for europiuni(III) and samarium(III) with 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione in solution are 0.4 pg l-1 and 0.3 ng l-1, respectively. The results are attributed to effective removal of the short-lived unwanted signals. This technique makes possible the ultratrace determination of a fluorescent molecule in a mixture with others by making the most of the difference of their emission lifetimes. The europium(III) complex can be determined with high selectivity and sensitivity in a large excess of the samarium(III) complex 相似文献
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20.
P. Melnikov I. V. Arkhangelsky V. A. Nascimento A. F. Silva L. Z. Zanoni Consolo 《Journal of Thermal Analysis and Calorimetry》2014,118(3):1537-1541
Thermal decomposition of samarium nitrate hexahydrate Sm(NO3)3·6H2O has been investigated by thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and X-ray diffractometry. This is a complex process that involves slow dehydration and fast concomitant internal hydrolysis. It is markedly different from the processes described for other members of the lanthanide series. At the first stage, pyrolysis is accompanied by removal of water and nitric acid to form samarium pentahydrate Sm(NO3)3·5H2O and intermediate oxonitrates containing O–Sm–OH groups. No traces of SmONO3 were detected. It is assumed that the existence of intermediate structures with six atoms of samarium best fits the experimental results. At higher temperatures, these products undergo further degradation, lose nitrogen dioxide, water, and oxygen, and finally, after having lost lattice water, are transformed into a cubic form of samarium oxide. 相似文献