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报导了芳族二硒醚在SmI_2作用下,Se—Se键还原断裂成硒负离子。再与α,β-不饱和酯(腈)发生Michael加成反应,得到β-硒代酯(腈)。 相似文献
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合成了两种单晶化合物二硫代酯1 和2,并对其经行了表征.二硫代酯1属于单斜晶系,空间群是P21/n; 二硫代酯2属于正交晶系,空间群是Pbca.此外,分别研究了两种二硫代酯在液态和固态中的荧光性能,发现二硫代酯1和2在乙腈溶剂中有很强的荧光,而在固体状态下没有荧光.这可能是由于在固态下分子间的堆积造成了荧光团发生迅速的π-π碰撞,从而导致荧光的自身淬灭. 相似文献
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在碱性条件下,聚邻二硒代苯被硼氢化钾还原成双硒离子后与二卤代和缩后关环得到7个邻苯二硒型硒杂冠醚化合物,其结构经元素分析、MS、IR和HNMR证实。 相似文献
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N,N-二(邻硝基苯氨基乙基)甘氨酸糖酯的合成 总被引:7,自引:0,他引:7
在氢氧化钠和四丁基溴化铵存在下,将N,N-二(邻硝基苯氨基乙基)甘氨酸分别与O-乙酰基溴代葡萄糖、O-乙酰基溴代半乳糖、O-乙酰基溴代乳糖和O-乙酰基溴代木糖作用,制得N,N-二取代甘氨酸的对应乙酰基糖酯。由元素分析、IR、MS和1HNMR确认了4个的糖酯的结构。关键词N,N-二(邻硝基苯氨基乙基)甘氨酸糖酯,溴代葡萄糖,溴代乳糖,溴代木糖,葡萄糖酸酯。 相似文献
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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
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钐试剂在有机合成中的应用 总被引:4,自引:0,他引:4
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。 相似文献
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Sm对MoO3-Bi2O3催化剂性能的影响 总被引:1,自引:0,他引:1
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。 相似文献
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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 总被引:2,自引:1,他引:2
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. 相似文献
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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 相似文献
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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%. 相似文献
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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. 相似文献
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TheaPPlicationofsamariumdiiodideinorganicSyntilesishasreceivedmoreandmoreattenhoninthelastdecade.'-'Itisapowerfulone-electrontr~ferreducest.Recently,wehaveconsideredthattheS-Stbondmightbereductivelycleavedwithsamariumdiiodide.Thiolestersareusefulintermediatesinorgbocchemistry.'-'Manynewmethodshavebeendevelopedforthepreparationoftlilolestersinrecentyears,'-"forexample,tilereachonbetWeensodiumthiobenzoateandarenediazoniumtetaluoroborates,'beatmentofnitrosoamidesornitroamideswithinercaptansint… 相似文献
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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