共查询到20条相似文献,搜索用时 125 毫秒
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利用改进的碱缩合或酸催化反应,合成了8种类杂芪染料:反式-(2-N-甲基吡咯基)-(4-N-甲基吡啶基)杂芪碘(反式-MPPSI)、反式-(2-吡咯基)-(4-N-甲基吡啶基)杂芪碘(反式-PPSI)、反式-(2-呋喃基)-(4-N-甲基吡啶基)杂芪碘(反式-FPSI)、反式-(2-噻吩基)-(4-N-甲基吡啶基)杂芪碘(反式-TPSI)、反式-(4-甲基)-4(4-N-甲基吡啶基)杂芪碘(反式- 相似文献
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合成酯基锡化合物的新方法酯基锡化合物(R'OCOCHRCH)nSnCl4-n(n=1,2。R=H,CH3。R'=烷基)是七十年代后期由英国Hutton小组首先开发出来的一类有机锡化合物[1],以它为中间体与巯基乙酸酯、硬脂酸、月桂酸等反应合成出了一类... 相似文献
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研究了1-(α-吡啶基)-5-苯基-3-(α-呋喃基)甲Zan在非离子表面活性剂吐温-80存在下与锌的显色反应,并将其应用于直接测定废和矿样中的微量锌,获得较为满意效果。 相似文献
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研究了1-(α-吡啶基)-5-苯基-3-(α-呋喃基)甲在非离子表面活性剂吐温-80存在下与锌的显色反应,并将其应用于直接测定废和矿样中的微量锌,获得较为满意效果。 相似文献
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烯丙基硅(氧)烷铂配合物硅氢加成催化剂的研究 总被引:12,自引:1,他引:11
通式为(CH2 CHCH2) nSiR(4- n) ( n = 2 ,3 ,4 ;R= Me ,Ph) 的烯丙基硅烷以及1 ,3 二烯丙基 四甲基二硅氧烷(DATM) 经由Grignard 反应制备,它们再与氯铂酸反应制备出相应的标题配合物,这种配合物可用做硅氢加成催化剂。研究发现在氯丙烯与硅氯仿的加成反应中,TAS( n = 4) 、DMDA(n = 2 ,R= Me) 、MTA( n = 3 ,R= Me) 和DATM 的铂配合物的活性都比氯铂酸大。同时还讨论了几种铂配合物催化剂对含氢硅油与乙烯基硅橡胶的加成反应活性,发现不同催化剂的活性各不相同。 相似文献
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微波辐射相转移催化合成茉莉醛 总被引:4,自引:0,他引:4
利用微波辐射结合相转移催化技术在无溶剂条件下苯甲醛与庚醛发生羟醛缩合反应制备茉莉醛。最佳反应条件为 :0 15 g氢氧化钾为碱 ,4 0 0g氧化铝为载体 ,三乙基苄基氯化铵(TEBAC)为相转移催化剂 ,n(PhCHO)∶n(n C6H13CHO)∶n(TEBAC) =2 5 0∶1 0 0∶0 2 5 ,辐射功率 5 6 0W ,辐射时间 6 0s ,茉莉醛的产率达 90 4%。在同样的条件下 ,苯甲醛与辛醛、苯乙酮发生羟醛缩合反应合成了α 己基肉桂醛和查尔酮 ,产率分别为 82 8%和 78 8% 相似文献
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α-呋喃丙烯酸的合成研究 总被引:6,自引:0,他引:6
在吡啶介质中 ,以六氢吡啶为缩合剂 ,通过糠醛与丙二酸的Knoevenagel缩合反应合成了α 呋喃丙烯酸 ,并对影响产率的因素进行了研究。结果表明 ,当n(糠醛 )∶n(丙二酸 )∶n (吡啶 )∶n (六氢吡啶 ) =1 0 0 0∶1 40 0∶2 40 0∶0 0 2 5时 ,在 95℃下反应 2 5h ,呋喃丙烯酸的产率为92 8% ,质量分数为 99 5 %。 相似文献
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他唑巴坦合成中1,3-偶极环加成反应的研究 总被引:2,自引:0,他引:2
以 6 氨基青霉烷酸为原料 ,经多步化学反应合成了他唑巴坦并重点研究了其中的 1,3 偶极环加成反应。首先由 6 氨基青霉烷酸通过重氮化 -溴化、氧化、保护、还原去溴得到了青霉烷酸二苯甲酯亚砜 ,每步反应的收率都在 90 %以上 ,然后与 2 巯基苯并噻唑反应得双硫开环物 ,收率为 99% ,再分别与无水氯化铜、叠氮化钠、高锰酸钾反应得到 2 β 叠氮甲基青霉烷酸二苯甲酯二氧化物 ,三步总收率为 30 % ,接着以醋酸乙烯作为环合试剂进行 1,3 偶极环加成反应制得 2 β 三唑甲基青霉烷酸二苯甲酯二氧化物 ,收率为 70 % ,最后经间甲酚脱保护得到了他唑巴坦 ,收率为 6 3%。整个反应经中试放大 ,总收率达 8.0 %以上 相似文献
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Karolina Klonowska–Wieszczycka Andrzej Olszanowski Anna Parus Barbara Zydorczak 《溶剂提取与离子交换》2013,31(1):50-62
Abstract: The model oximes of 1‐(2‐pyridyl)undecane‐1‐one (2PC10), 1‐(2‐pyridyl)tridecane‐1‐one (2PC12) and 1‐(4‐pyridyl)tridecane‐1‐one (4PC12) were synthesized and used for copper(II) extraction from chloride solutions. The behavior of these ligands towards copper(II) extraction was investigated for different experimental conditions with a particular emphasis on the influence of the concentrations of copper ions, chloride ions, and ligand. The obtained results indicated the ability of pyridylketoximes to extract copper(II) from chloride solutions. 2‐Pyridyl ketone oximes are stronger extractants of copper than 4‐pyridyl ketone oximes. Copper can be effectively stripped by water or diluted sulfuric acid. 相似文献
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硝苯地平口服渗透泵片的制备及其体外释药特性 总被引:8,自引:3,他引:8
研制了单室单层硝苯地平口服渗透泵片 ,考察了片剂配方和主要制备参数、实验条件参数对药物释放速率的影响。在大量实验基础上 ,对硝苯地平口服渗透泵片的配方和制备参数进行优化 ,所确定的最优片芯配方为 (以片为基准 ) :硝苯地平 30mg ,β 环糊精 98 3mg ,聚环氧乙烷10mg ,聚乙烯吡咯烷酮 2 1 2 5mg ,渗透活性物质 14 0 4mg ;最佳孔径为 5 0 0 μm。依据最优方案制备的硝苯地平口服渗透泵片经体外释放度测定表明 ,在 2 1h内该渗透泵制剂形态稳定 ,具有良好的零级释放特性 相似文献
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BACKGROUND: Ethylene oligomerization is the major industrial process to produce linear α‐olefins. Recently much work has been devoted to late transition metal catalysts used in this process, especially those with 2,6‐bis(imino)pyridyl dihalide ligands. Considering that most work has focused on simple modification to the substituents in imino‐aryl rings based on the symmetric bis(imino)pyridyl framework, here we expand this work to the asymmetric mono(imino)pyridyl ligands. RESULTS: The preparation, structure and ethylene polymerization/oligomerization behavior of series of mono(imino) pyridyl–MCl2 and bis(imino)pyridyl–MXn complexes are presented. The systematic studies were focused on the relationship between the catalytic behavior of these complexes for ethylene polymerization/oligomerization and reaction conditions, ligand structures, metal centers and counter‐anions. The influence of the coordination environment on catalyst behavior is also discussed. CONCLUSION: For mono(imino)pyridyl–Co(II) and ? Ni(II) catalysts bearing the Cl? counter‐anion, good activities ranging from 0.513 × 105 to 1.58 × 105 g polyethylene (mol metal)?1 h?1 atm?1 are afforded, and the most active catalysts are those with methyl in both ortho‐ and para‐positions of the imine N‐aryl ring. For bis(imino)pyridyl–Co(II) and ? Ni(II) catalysts bearing the SO42? and NO3? counter‐anions, the low activities for ethylene oligomerization are in sharp contrast to those of their chloride analogues. Copyright © 2009 Society of Chemical Industry 相似文献
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Petr Zimcik Miroslav Miletin Veronika Novakova Kamil Kopecky Zuzana Dvorakova 《Dyes and Pigments》2009,81(1):35-39
Zinc tetrapyrazinoporphyrazines comprising different numbers of pyridin-2-yl and tert-butylsulfanyl substituents were prepared by the statistical condensation of two precursors – 5,6-bis(tert-butylsulfanyl)pyrazine-2,3-dicarbonitrile (A) and 5,6-dipyridin-2-yl-pyrazine-2,3-dicarbonitrile (B). The ensuing zinc tetrapyrazinoporphyrazines were chromatographically separated on silica column and characterized. Adjacent (AABB) and opposite (ABAB) isomers were not separated. The prepared zinc tetrapyrazinoporphyrazines did not differ in their Q-band position but the B-band position was shifted hypsochromically for compounds bearing more pyridyl units; in addition, a weak band at 450–520 nm decreased with increasing number of pyridyl substituents. Singlet oxygen quantum yields (ΦΔ in the range 0.69–0.53) decreased with increasing number of pyridyl units on the macrocyclic core, while fluorescence quantum yields showed the reverse tendency (ΦF in the range 0.22–0.26). 相似文献