钐试剂在有机合成中应用的若干新进展

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.     

钐试剂在有机合成中的应用

钐试剂在有机合成中的应用是近年来有机合成方法学研究中的热点之一。综述了十余年来本课题组在钐试剂应用于有机合成方面所开展的有关工作：(1)二碘化钐作为偶联剂和还原剂在有机合成中的应用;(2)金属钐直接应用于有机合成;(3)三碘化钐作为路易斯酸应用于有机合成;(4)有机钐试剂在有机合成中的应用。     

Sm对MoO3-Bi2O3催化剂性能的影响

在MoO3-B i2O3催化剂中加入稀土氧化物Sm2O3,在固定床反应器中考查了Sm2O3添加量、反应温度、异丁烯浓度、原料气流量等对异丁烯转化为甲基丙烯醛反应的影响。实验表明,添加Sm2O3可明显提高异丁烯的转化率和甲基丙烯醛的选择性。用XRD技术研究了催化剂的组成,Mo-B i-O催化剂的成分主要是B i2O3和MoO3的混合物,添加Sm后出现了Sm2Mo3O12的衍射峰,且衍射峰的强度随着Sm添加量的增加而增强。     

钐、铕-四环素类抗生素络合物荧光性能的研究及其在荧光分析中的应用

本文探讨了钐、铕-四环素、强力霉素、土霉素、金霉素络合物的荧光性能及利用该体系以荧光分析光度法测定痕量钐和铕的可能性与最佳测定条件.结果表明:在高碱度条件下(pH12～1.0mol/L NaOH),以四环素体系的稳定性、灵敏性最好,钐和铕的检测限分别为38.2和0.09ng/mL.     

Samarium diiodide induced reductive cleavage of the Te–Si bond in phenyltellurotrimethylsilane: A novel method for the synthesis of alkylphenyl tellurides,telluroesters, and β‐phenyltelluro esters (nitriles)

Phentyltellurotrimethylsilane (1) was reduced by samarium diiodide in tetrahydrofuran (THF) to produce samarium phenyltellurolate. This new tellurolate anion reacted smoothly with alkyl and benzyl halides to give alkyl and benzyl‐phenyl tellurides in good yields under mild and neutral conditions. The samarium tellurolate also reacted with acyl halides or anhydrides to give telluroesters, and the 1,4‐addition of samarium tellurolate to α, β‐unsaturated esters (nitriles) gave β‐phenyltelluro esters (nitriles). © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 471–474, 1999     

Reductive Cleavage of the S-Si Bond in Phenylthio-trimethylsilane:A Novel Method for the Synthesis of Thiolesters

TheaPPlicationofsamariumdiiodideinorganicSyntilesishasreceivedmoreandmoreattenhoninthelastdecade.'-'Itisapowerfulone-electrontr~ferreducest.Recently,wehaveconsideredthattheS-Stbondmightbereductivelycleavedwithsamariumdiiodide.Thiolestersareusefulintermediatesinorgbocchemistry.'-'Manynewmethodshavebeendevelopedforthepreparationoftlilolestersinrecentyears,'-"forexample,tilereachonbetWeensodiumthiobenzoateandarenediazoniumtetaluoroborates,'beatmentofnitrosoamidesornitroamideswithinercaptansint…     

Simultaneous determination of samarium, europium and terbium with quinaldic acid and phenanthroline by synchronous derivative fluorimetry

Synchronous derivative fluorescence of samarium, europium and terbium complexes with quinaldic acid and phenanthroline was examined in aqueous solution. The composition of these complexes was determined. The maximum emission wavelengths are 645 nm, 617 nm and 545 nm for samarium, europium and terbium, respectively. Under the optimal experimental conditions, the fluorescence intensity was a linear function of concentration in the range of 10-250 ppm for samarium, 0.5-50 ppm for europium and 0.5-300 ppm for terbium. Simultaneous determination of samarium, europium and terbium was successfully carried out for samarium oxide and middle rare earth mixture. The precision of the method, expressed as relative standard deviation, is within 1.1-2.5%.     

二碘化钐在有机合成中的应用新进展

综述了2005年以来二碘化钐在有机合成中应用的新进展,主要涉及二碘化钐在还原偶联反应以及作为预催化剂方面的一些新的应用.     

Crystallization of new samarium polyborates

Rare earth borates are important due to their excellent properties, especially for optics. Here, we report the hydrothermal synthesis and structural determination by single-crystal X-ray diffraction of two new samarium polyborates with layered structures, being constituted by hexaborate chains. These hexaborate chains are connected by samarium polyhedra, forming dense sheets that further interact with each other by hydrogen bonding via isolated boric acid between these sheets. The third phase possesses a three-dimensional framework structure. The thermal stability of selective samples has been studied. The crystallization of samarium borate depends highly on the experimental conditions. Three samarium polyborates have been crystallized in very similar experimental conditions, clearly indicating that new lanthanide borate compounds with tailored structures may be prepared in the future by careful choice of physicochemical conditions.     

Synthesis of nano-pore samarium (III)-imprinted polymer for preconcentrative separation of samarium ions from other lanthanide ions via solid phase extraction

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.     

Application of samarium reagents in organic synthesis

Application of samarium diiodide, samarium triiodide, Sm0/auxiliary system and organosamarium reagents in organic synthesis was reviewed.     

A new strategy for the synthesis of α,β-diaroylpropionates promoted by samarium metal in DMF

When promoted by samarium in DMF, aroyl chlorides react readily with acrylates to afford α,β-diaroylpropionates in good to excellent yields without pretreating or activating the metallic samarium.     

Influence of samarium on the hydrogenation properties of supported nickel catalyst

The effect of samarium on Ni/sepiolite catalyst was investigated by benzene hydrogenation, methanation of carbon dioxide, CO chemisorption, XPS and CS₂ poisoning, respectively. The result indicates that a proper amount and impregnation order of samarium in the preparation of Ni-Sm/sepiolite catalyst are very efficient to improve the catalytic activity and anti-sulfur ability. At the same time, the mechanism of samarium improving hydrogenation activity of Ni/sepiolite is presented.     

Selective accumulation of light or heavy rare earth elements using gram-positive bacteria

The accumulation of samarium from a solution only containing samarium by Arthrobacter nicotianae was examined. The amount of accumulated samarium was strongly affected by the concentration of samarium and pH of the solution. The accumulation of samarium by the strain was very rapid and reached equilibrium within 3 h. The accumulation of samarium-europium or europium-gadolinium from the solution containing the two metals using various actinomycetes and gram-positive bacteria was also examined. Most of the tested strains could accumulate similar amounts of samarium and europium; however, most of the tested strains could accumulate a greater amount of europium than gadolinium. Especially, the amounts of accumulated europium using gram-positive bacteria were higher than those using actinomycetes. The selective accumulations of light or heavy rare earth elements (REEs) using A. nicotianae and Streptomyces albus were also examined. The amounts of accumulated samarium and europium were higher than those of the other light REEs using both microorganisms. S. albus can accumulate greater lutetium than other REEs from a solution containing yttrium and eight heavy REEs. On the other hand, A. nicotianae can accumulate higher amounts of terbium and ytterbium than that of the other heavy REEs from the same solution. A. nicotianae can also accumulated higher amounts of Sm than other REEs from a solution containing six light REEs.     

非水凝胶原位聚合法制备含钐PMMA材料的研究

将无水三异丙氧基钐直接加入甲基丙烯酸甲酯（MMA）中会迅速形成凝胶,通过原位聚合可获得含钐的PMMA固体材料.研究表明,随钐含量的提高,含钐PMMA的结构逐渐由线型向交联网状体型转变,并使材料耐热性、耐溶剂性及贮能模量提高;ESEM表明,含钐PMMA呈交联网络蜂窝结构,未见聚集体,钐元素在体系中均匀分布;同时该材料呈现钐离子的特征荧光,在所测定的浓度范围内,荧光强度随钐含量增加而提高.     

Temperature-controlled selective reduction of arenesulfonyl chlorides promoted by samarium metal in DMF

Promoted by samarium in DMF, arenesulfonyl chlorides can be selectively reduced to diaryldisulfones, diarylthiosulfonates and diaryldisulfides in good to excellent yields by reaction temperature control without the need to pretreat or activate the metallic samarium.     

Synthesis of Enamines via the Cross-coupling of Thioamides and Diarylketones Promoted by the Sm/SmI2 Mixed Reagent

Since 1977 samarium diiodide has been widely used to promote a lot of reductive and coupling reactions1. Utilizing the samarium/samarium diiodide mixed reagent, Ogawa performed the intermolecular reductive deoxygenative coupling of amides2. Our group has …     

Synthesis of new luminescent materials activated with divalent samarium

A simple technique for the preparation of powder compounds doped with divalent samarium is described. The reaction is carried out in nickel containers sealed in an inert atmosphere. The samarium impurity is introduced as samarium trifluoride SmF₃, and metallic samarium powder acts as the reducing agent to change Sm³⁺ into Sm²⁺. Using this method, samarium has been stabilized in the divalent state in various fluorides: KMgF₃, BaLiF₃, BaY₂F₈, and KY₃F₁₀. The resulting compounds show under ultraviolet or visible excitation an intense luminescence in the red region characteristic of Sm²⁺-doped materials. The emission and excitation spectra of these phosphors are presented and briefly discussed.     

二碘化钐在脱氧、还原和碳-碳键形成反应中的应用

本文研究了二碘化钐对一些有机化合物的脱氧反应, 以及它在醇存在下对α-卤代酮、偶氮苯和苯醌的还原反应。首次报道了在二碘化钐作用下α-卤代酮与醛之间的碳-碳键形成瓜在, 高产率地制备了各种α,β-不饱和酮; 同时提出了涉及由α-卤代酮同时与Sm(II)和Sm(III)/I^-物种作用形成烯醇钐盐中间体的可能机理。     

二碘化钐促进的硒代酯的合成

用SmI2/THF/HMPA体系在室温下使二芳基二硒醚中的Se-Se键还原断裂成硒负离子物种, 继而与酸酐作用得到硒代酯, 该反应条件温和中性, 产率良好, 提供了合成硒代酯的一个新途径。