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Tsutomu Kawai Yoichi Kodera Shigeru Oae Masahiro Ishida Takashi Takeda Shoji Wakabayashi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):139-148
Abstract Ligand coupling reactions take place not only between benzyl and 2-pyridyl groups and two 2-pyridyl groups in the treatment of benzyl, alkyl and aryl 2-pyridyl sulfoxides with Grignard reagents, but also between such groups as p-benzenesulfonylphenyl, 4-pyridyl, 2-quinolyl and 2-pyrimidyl, and the benzyl group. There are cases in which ligand exchange precedes ligand coupling, especially with 2-heteroaryl groups. In addition, even some alkyl groups were found to couple with the 2-pyridyl group. The ease of coupling seems to be associated with the electronegativity of the coupling carbon atom of the ligand, when one compares the 13C NMR chemical shifts. 相似文献
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P. Monjoint G. Guillot M. Laloi-diard 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):192-197
Abstract The rate of nucleophilic reaction of anions and amines with p-nitrophenyltosylate has been determined in a 41% w/w ethanol-water mixture at 25°. For weakly basic amines, the reaction is general base and general acid catalyzed. Aldoximates and thiophenolate show an enhanced nucleophilicity compared to phenolates of same basicity. The results are interpreted in terms of charge and frontier controlled reactions. 相似文献
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Jing-Lin Zhang Xiao-Bo Ma 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):15-20
Abstract The title reaction was investigated to find that only substitution reaction on amino group occurred when (2-benzothiazolyl)sulfenamides 1 reacted with P(NR2,)3, whereas the treatment of 1 with (RO)P(NR2,)2, gave derivatives of phosphorodiarnidothioic acid together with 2-alkylthiobenzothiazole and its isomer in addition to substitution products, and no substitution products obtained when N-substituted analogues of 1 were treated similarly. 相似文献
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三苯基丙烯腈与格氏试剂RMgBr或烷基锂RLi(R=n-C4H9,n-C5H11,n-C6H13)反应的主要产物是烷基取代三苯乙烯(3)和烷基取代三苯基丙腈(4).它们的结构经元素分析以及IR,NMR,UV,MS等测定分别予以确定.3和4分别经置换及共轭加成反应而生成. 相似文献
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金属有机配合物对格氏试剂与酰氯交叉偶联反应的催化活性 总被引:1,自引:0,他引:1
本文采用镍-膦配合物、有机钛化合物、氯化钕、乙酰丙酮希土配合物、含二茂铁基羰基三氟丙酮希土配合物(HL)_3Ln·xH_2O共十余种,作为苯甲酰氯与正丁基格氏试剂的交叉偶联反应的催化剂,发现各种有机钛化合物都具有和经典镍膦配合物类同或略好些的催化活性,而(HL)_3Ln,当Ln为Ce、Pr、Nd、Sm、Ho、Er时,均表现良好催化活性,反应产率高,反应选择性很好(~100%),本文同时讨论了反应的催化作用过程。 相似文献
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C. Owens R. Hall T. Mitchell D. Chasen L. Gelfand L. L. Pytlewski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):177-180
Abstract Sym-dichloro-bis(2,4,6-trichlorophenyl) urea reacts explosively with dimethyl sulfoxide to yield phosgene, formaldehyde, methane, sulfur dioxide, ethylene chloride, methylene dichloride, chlorinated disulfides, and insoluble bis(2,4,6-trichlorophenyl) urea. The products, other than bis(2,4,6-trichlorophenyl) urea, are separated and characterized by means of gas chromatography and mass spectrometry. A homolytic mechanism is proposed for the reaction. 相似文献
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某些单偶氮类新显色剂与铝离子显色反应的研究 总被引:3,自引:0,他引:3
以变色酸和H酸为母体设计合成了19个单偶氮类试剂,分别考察了它们与铝离子的显色反应,对试剂结构与光度性能的关系作了探讨,为寻求新的性能优良的测铝是色剂提供了依据。 相似文献
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在pH 5 .5溶液中 ,有溴化十六烷基三甲基铵存在下 ,钪 (Ⅲ )与乳酸及埃络青R(ECR)形成胶束混酸络合物 ,该络合物最大吸收波长为 5 90nm ,表观摩尔吸光系数ε =1.2 6× 10 5L·mol- 1·cm- 1。络合物的组成为钪 (Ⅲ )∶乳酸∶ECR =1∶1∶2。由于乳酸的存在 ,显色体系的灵敏度、选择性和稳定性都得到提高。用 1 苯基 3 甲基 4 苯甲酰基吡唑啉酮 5 (PMBP)分离干扰组分后 ,可测定钨矿及其浸出渣中的微量钪 ,结果满意 相似文献
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Polymeric Grignard Reagent (PGR) based on the chloromethylated poly(ST-co-DVB) resinhas been prepared by means of anthracene-magnesium complex in THF (Anth-Mg-THF), andpolymer matrix with long polymethylene spacer was synthesized via the coupling reaction betweenPGR and α, ω-dibromoalkanes. Based on the studies of factors affecting the coupling, such ascatalyst,reaction time,the length of spacer etc.,this paper offers the optimal reaction conditionsand three typical experiment procedures. The mechanism for the formation and coupling reactionof PGR are also discussed. 相似文献
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脱乙酰甲壳质和卡拉胶在溶液中的反应及其复合物性质研究 总被引:1,自引:0,他引:1
脱乙酰甲壳质(CTS)和卡拉胶(CGN)在溶液中反应生成不溶于水的沉淀,红外光谱分析及相反离子含量测定证明,CTS和CGN分子间的联结是以CTS分子中的-NH_3~+与CGN分子中的-SO_3~-通过静电相互作用来实现的。形成的聚电解质复合物N/S摩尔比在较宽的范围内依赖于反应混合溶液组成比、pH值及CTS的脱乙酰度。不同条件下形成的复合物具有不同的形态结构,当CTS分子与CGN分子上的电荷密度接近时,电镜观察到的复合物呈纤维状结构。复合物不溶于二甲基亚砜及CH_3COCH_3/KBr/H_2O(20∶20∶60wt)三元溶剂,在加热时溶于浓甲酸和稀盐酸,其溶解性随CTS脱乙酰度的增加而降低,CTS和CGN形成的聚电解质复合物具有一定的抗血凝性。 相似文献
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用自旋捕捉技术与ESR相结合的方法研究了脂二胺在ZnO、TiO2的庚烷或苯的分散体系中光诱导的电子转移过程。观察到DMPO与氮中心自由基加合物的ESR信号,表明捕捉到的自由基是脂二胺与光生空穴作用而产生的胺的阳离子自由基。 相似文献
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新试剂1-偶氮苯基-3-(5-硝基-2-吡啶)-三氮烯的合成及其与镉的显色反应 总被引:29,自引:0,他引:29
三氮烯试剂是测定ⅠB、ⅡB族金属元素的优良试剂。近年来 ,对该类试剂中的取代苯重氮氨基苯的合成和分析应用报道较多[1 ,2 ] ,但对含杂环的三氮烯试剂的研究报道较少。我们曾将安替比林[3] 、苯并噻唑[4,5] 、噻唑[6] 引入该类试剂中 ,使试剂灵敏度有所提高。为进一步探讨此类试剂的分析性能 ,我们将 5 硝基吡啶引入 ,合成了 1 偶氮苯基 3 ( 5 硝基 2 吡啶 ) 三氮烯 (ABNPDT)。分子中含有杂环吡啶的同时还有强吸电子———NO2存在 ,另一端为具有长共轭链的偶氮苯基 ,这样更有利于试剂分子中电子的流动 ,从而改善分析性能。… 相似文献
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