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树脂固定化手性联萘酚-钛催化剂的合成及其催化特性研究 总被引:2,自引:0,他引:2
自从Merrifieled首创多肽的固相合成以来 ,以聚苯乙烯树脂为支持物的合成方法在化学及生物化学等领域得到广范应用[1~ 3] .作为该方法的一个新的发展方向 ,将手性配体联接在多聚物上用于非均相不对称催化已成为当前不对称合成的热门领域之一 .近年来踊现出大量多聚物固定化的手性不对称催化剂 ,在二乙基锌对醛的不对称加成[4] 及Diels Alder等[5] 反应中显示出优良的不对称催化能力 .光学活性的 1 ,1’ 联萘 2 酚 (BINOL)是不对称催化中应用最广泛的配体之一[6~ 9] .为了将BINOL引入非均相不对称催化 ,我… 相似文献
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聚合物负载的手性联二萘酚的合成及其在不对称催化中的应用进展 总被引:1,自引:0,他引:1
作为一种有机配体, 手性1,1'-联二萘酚(BINOL)被广泛应用于过渡金属催化的均相不对称有机反应. 为克服均相催化剂不易回收重复使用等缺陷, 人们深入研究了聚合物负载手性BINOL催化剂的方法. 总结了近年来聚合物负载手性BINOL催化剂的合成及其在不对称有机催化中的应用, 并对负载型BINOL催化剂进行了展望. 相似文献
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光学活性的 1,1′ 联 2 萘酚 (BINOL)及其衍生物作为优异的手性配体应用于不对称催化中已取得了巨大进展 ,显示出广阔的应用前景 .对BINOL小分子和高分子在各种不对称催化反应中的最新进展和发展方向进行了评述 ,并介绍了有关BINOL的几种新型催化策略 相似文献
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使用(+)-苯丙胺和CuCl2.2H2O形成的配合物为手性催化剂,以3-羟基-2-萘甲酸甲酯(1)和2,7-萘二酚(2)进行反应,得到对映体过量的联萘酚衍生物2,2′,7′-三羟基-1,1′-联萘-3-甲酸甲酯(3),采用加入手性双噁唑啉噻吩化合物(4)为诱导试剂的1H-NMR的方法测定化合物(3)的ee值. 相似文献
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报道了树状结构的手性联二萘酚(BINOL)配体的合成及其在二乙基锌对醛的不对称加成反应中的应用.(R)-2,2′-二羟基-1,1′-联萘-3,3′-二羧酸与末端为氨基的Frechet聚芳醚型树状分子经缩合反应,以中等产率得到0~3代的树状分子配体,用1HNMR,IR和MALDI-TOF质谱进行了结构表征.这些树状手性配体与Ti(OPri)4在无水甲苯溶液中形成的配合物是二乙基锌对醛不对称加成反应的高效催化剂,树状分子载体的体积对催化剂的对映选择性没有明显的影响.以邻氯苯甲醛为底物时,反应的对映选择性随树状分子代数的增加而有所提高. 相似文献
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ZHANG Zhengpu HUANG Jinxia LI Mingxia HU Yushan HE Binglin 《Chinese Journal of Reactive Polymers》1999,(Z1)
1INTRODUCTIONQ--AminoacidsarefoundationStonesofallproteins,butonlyL--aminoacidscanbesynthesizedintoproteinsbyorganisms.ThespecialconfigUrationofD--aminoacidmayimprovetheactivitiesofsomepeptidepharmaceuticalsbymanytimes.TheimportanceofthestereoconfigurationofQ--aminoacidscouldbeillustratedbytheabovetWoexamples.Fig.ITheAsymmetricAlkylationofN-diphenylmethleneGlycinet-butylEster.Inpreviouswork,wehavereportedthatpolymer-supportedquiniumandcinchoniniumsaltswereusedasphasetransfercatalyst… 相似文献
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Chiral polymers P-1 and P-2 were synthesized by the polymerization of (R)-3,3'-diiodo-2,2'-bisbutoxy-1,1'- binaphthyl (M- 1 ) with 2,5-di(4-ethynylphenyl)- 1,3,4-oxadiazole (M-3) and (R)-3,3'-diethylnyl-2,2'-bisbutoxy- 1,1 '-binaphthyl (M-2) with 1,2-di(4-bromophenyl)acetylene (M-4) under Sonogashira reaction, respectively. Both monomers and polymers were analyzed by NMR, MS, FT-IR, UV-Vis spectroscopy, DSC-TGA, fluorescence spectroscopy, GPC and CD spectroscopy. CD spectra of P-1 and P-2 are similar due to the same chiral center units and main chain structure. The long wavelengths CD effect of P-1 and P-2 can be regarded as the more extended conjugated structure and a highly rigid backbone in the polymer chain. Polymers have strong blue fluorescence due to the efficient energy migration from the extended n-electronic structure of the polymers to the chiral binaphthyl core and are expected to provide understanding of the relationship between molecular structure and fluorescent property of the chiral polymers. 相似文献
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Henri B. Kagan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):127-132
Abstract The main chemical or enzymatic methods of asymmetric oxidation of sulfides are reviewed. A new approach to chiral sulfoxides is described, which uses tertiobutyl hydroperoxide in presence of a chiral titanium complex. The results obtained during the last two years are summarized. The best enantiomeric excess amounts to 95% in the case of formation of cyclopropyl phenyl sulfoxide. 相似文献
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单体(R)-3,3′-二碘-2,2′-二正丁氧基-1,1′-联萘((R)-M-1),(R)-6,6′-二溴-2,2′-二正丁氧基-1,1′-联萘((R)-M-2)分别与1,4-二乙烯基-2,3-二丁氧基萘(M-3),在钯催化下,通过Heck交叉耦合反应合成手性高分子P-1与P-2.单体和高分子进行了1H-NMR1、3C-NMR、FT-IR、旋光度、GPC、UV、热分析、荧光光谱和CD等测试分析.高分子侧链上引入丁氧基后使得手性高分子溶解性增强并具有良好的成膜性,手性高分子P-1和P-2都能发射较强的蓝绿色荧光,荧光量子效率分别为0.42和0.48. 相似文献
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Four polymer-supported Fe-Co tetrametallic clusters have been prepared by ion exchange and ligand exchange. Their structures were characterized by IR, UV/visible diffuse reflectance spectra and elemental analysis, and by analogy with the reference cluster PhCH_2NMe_3FeCo_3 (CO)_2 . The four heterogenous clusters were efficient catalysts in the hydroformylation of 1-hexene, turnover numbers amounted to 823 —924 with the yield of 83.2—92.4% heptyl aldehydes and ratios of normal aldehyde to iso-aldehyde of 1.2—1.6, they are facilitated forming the normal aldehyde in comparison with the homogeneous analogue. For the polymer-supported clusters prepared by ion exchange, the polymer-cation parts had no obvious effect on the activity of the cluster anion. The polymer-phosphine substituted cluster prepared by ligand exchange was more stable than the clusters preparedby ion exchange. 相似文献
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The optical α-amino acids were synthesized under room temperature byalkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phasetransfer conditions using polymer-supported cinchonine (or quinine) alkaloids as chiralphase transfer catalysts and dichloromethane as solvent, followed by hydrolysis of theabove intermediates introduced to the final products-optical α-amino acids. This is anew method for the asymmetric synthesis of α-amino acids. The influences of catalyst,temperature, substrates, and organic solvents on the chemical yield and optical purities ofproducts were studied. 相似文献
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