共查询到18条相似文献,搜索用时 109 毫秒
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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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新型杂环三氮烯荧光试剂1,8-双(2-苯并噻唑重氮氨基)萘的合成及其分析应用 总被引:1,自引:1,他引:0
将1,8-萘二胺和苯并噻唑类试剂结合, 并引入杂环三氮烯结构, 合成了新荧光试剂1,8-双(2-苯并噻唑重氮氨基)萘(BBTANP), 其结构经红外光谱、核磁共振谱和元素分析证实. 研究结果表明, 在碱性介质中, 该试剂与Cu(Ⅱ)形成1∶1的络合物, 并在λex/λem=362 nm/459 nm处产生荧光增强作用. 据此建立了BBTANP测定Cu(Ⅱ)的新型荧光分析法, 该方法的线性范围为8.0×10-7—1.0×10-5 mol /L, 检测限为1.3×10-7 mol/L. 将其应用于水样中Cu(Ⅱ)的测定, 结果令人满意. 相似文献
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考察了固体碱不同的碱性位对丙酮和碳酸二甲酯反应的影响,并对反应在不同碱性位上的反应机理进行了推测.实验结果表明,由表面羟基引起的弱碱位有利于丙酮自身缩合反应的进行,主产物为二丙酮醇、4-甲基-3-戊烯-2-酮和4-甲基4-戊烯-2-酮;Lewis酸碱离子对有利于碳酸二甲酯的甲基化反应的发生,主产物为2-甲氧基丙烯;而由固体碱表面配位不饱和的O^2-所造成的强碱位有利于碳酸二甲酯的甲氧基羰基化产物的生成,主产物为乙酰乙酸甲酯;同时发现各种产物的收率与对应的各碱性位的碱量之间均具有较好的线性关系. 相似文献
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1,8-萘啶氮氧化物(简写napyo)是一种配位能力较强的中性配体,关于它与金属离子形成的配合物已有报道.但工作主要集中在配合物的合成及性质的研究,它与金属离子形成的配合物的晶体结构至今未见报道.本工作旨在探讨1,8-萘啶氮氧化物与铜(Ⅱ)的配合物中配体与金属离子的配位情况以及铜(Ⅱ)的配位构型. 相似文献
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Fu-kui Xiao De-sheng Zhang Qing-nian Dong Wei Wei and Yu-han Suna 《Reaction Kinetics and Catalysis Letters》2006,89(1):131-138
Summary The FT-IR characterization showed that anhydrous zinc acetate hardly interacted with dimethyl carbonate, but it could coordinate
with 1,5-naphthalene diamino to form a new complex. As a result, a new mechanism on 1,5-naphthalene diamino activation was
proposed for the methoxycarbonylation of 1,5-naphthalene diamino with dimethyl carbonate over anhydrous zinc acetate. 相似文献
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Chin-Ping Yang Wen-Tung Chen 《Journal of polymer science. Part A, Polymer chemistry》1993,31(6):1571-1578
A new bis(phenoxy)naphthalene-containing diamine, 1,5-bis(4-aminophenoxy)naphthalene, was synthesized in two steps from the condensation of 1,5-dihydroxy-naphthalene with p-chloronitrobenzene in the presence of potassium carbonate, giving 1,5-bis(4-nitrophenoxy)naphthalene, followed by hydrazine hydrate/Pd? C reduction. A series of polyamides and copolyamides were synthesized by the direct polycondensation of the diamine with various aromatic dicarboxylic acids or with mixed dicarboxylic acids in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. The polymers having inherent viscosity of 0.81–1.25 dL/g were obtained in quantitative yield. Most of the polymers were generally soluble in aprotic solvent such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, etc. The polymers derived from rigid dicarboxylic acids such as terephthalic acid, naphthalene dicarboxylic acid, and 4,4′-biphenyldicarboxylic acid exhibited crystalline patterns. Glass transition temperatures of polymers were in the range of 230–360°C, and 10% weight loss temperatures in nitrogen and air were above 492 and 470°C, respectively. © 1993 John Wiley & Sons, Inc. 相似文献
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Jingjing Jiang Dr. Yves Queneau Prof. Dr. Florence Popowycz 《European journal of organic chemistry》2023,26(19):e202300144
The use of the renewable platform molecule 5-hydroxymethylfurfural (5-HMF) in multi-component reaction with a diamine and an alkynone to generate seven-membered 1,5-benzodiazepines is described. Due to the sensitivity of 5-HMF to strong acidic and basic conditions, the investigation required an in-depth revisit of reaction parameters as compared to benchmark aldehydes. Among catalysts/solvents couples, ammonium acetate in ethanol proved to be a clean and efficient system. These optimized conditions were subsequently used to investigate the scope of the reaction providing a library of 1,5-benzodiazepines in moderate to good yields from a wide range of diversely substituted diamines and alkynones or alkyl alkynoates. 相似文献
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Summary Separation of positional and cis-trans-isomers of tetrahydro-1,5-benzothiazepines and tetrahydro-1,5-benzodiazepines was studied using reversed-phase chromatography and liquid-solid chromatography. The selection of solvent was based on the selective triangle for solvents. Systems of separation consisted of C18 columns and methanol, THF or acetonitrile in water for the reversedphase method; it was suitable for the separation of positional isomers only but the liquid-solid method was suitable for separation of cis-trans-isomers as well as positional isomers using a silica column and ethyl ether, chloroform or ethyl acetate as the mobile phase respectively. 相似文献
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A green synthetic method for 1,5‐disubstituted carbohydrazones is described. The reaction of dimethyl carbonate with hydrazine hydrate first gave carbohydrazide, which further reacted with various aromatic aldehydes or aliphatic ketones under solvent‐free conditions to efficiently afford 1,5‐disubstituted carbohydrazone. This protocol has the advantages of using nontoxic dimethyl carbonate as starting material, no use of organic solvents, short reaction time, high yield, and simple workup procedure. 相似文献
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Lili Wang Eiry Kobatake Yoshihito Ikariyama Masuo Aizawa 《Journal of polymer science. Part A, Polymer chemistry》1993,31(11):2855-2861
Bilirubin oxidase (EC1.11.1.7) was used to catalyze the oxidative polymerization of 1,5-dihydroxynaphthalene to its polymer in a mixed solvent composed of dioxane, ethyl acetate, and acetate buffer. In an aqueous solution, the enzymatic oxidative polymerization hardly occurred and resulted in negligible yield mainly due to the poor solubility of 1,5-dihydroxynaphthalene. In the mixed solvent the conversion proceeded with a yield of ca. 70%. The polymer yield was studied with respect to reaction time and solvent components. Elemental analysis, UV-visible, fluorescent, and FT-IR spectroscopic analyses, proton NMR and electrochemical studies, and solubility in various organic solvents revealed that 1,5-dihydroxynaphthalene is polymerized by the C? C coupling. The molecular weight of the polymeric products solubilized with DMF varied from low molecular weight product to high molecular weight polymer. From the chromatographic studies, the organic solvent–insoluble residue was suggested to be highly polymerized material. Based on these findings a possible mechanism for enzymatic polymerization of 1,5-dihydroxynaphthalene is presented: less stable intermediates produced enzymatically from 1,5-dihydroxynaphthalene undergo coupling and polymerization to ortho-1,5-dihydroxynaphthalene polymer, thereby resulting in a regioselective polymerization of 1,5-dihydroxynaphthalene. © 1993 John Wiley & Sons, Inc. 相似文献
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According to the Ullman reaction mechanism, the synthesis of 1,5-di(o-anisidino)anthraquinone was achieved by the multiphase reaction of 1,5-dichloroanthraquinone in xylene and o-anisidine in the presence of copper metal powder and potassium acetate. The effects of various factors on the reaction, such
as the dosages of xylene and catalyst, molar ratios of raw materials, and reaction times were investigated. When the molar
ratio of 1,5-dichloroanthraquinone to o-anisidine and potassium acetate is 1:10:2.5 and the catalyst dosage based on 1,5-dichloroanthraquinone is 5.3%, the conversion
of 1,5-dichloroanthraquinone is 97.8% and the yield of 1,5-di(o-anisidino)anthraquinone is 80.6% after reflux for 10 h. Under these conditions, the recovery of the solvent is 86.0%. The
target compound was identified by MS, 1H NMR, IR and DSC.
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Translated from Journal of Dalian University of Technology, 2007, 47(2): 170–174 [译自: 大连理工大学学报] 相似文献
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Hidetsugu Wakabayashi Teruo Kurihara Kimio Shindo Masaaki Tsukada Paw-Wang Yang Masafumi Yasunami Tetsuo Nozoe 《中国化学会会志》1998,45(3):391-400
A very convenient, one-pot synthesis (over 80% yield) of 3-bromo-1,5- and ?1,7-azulenequinones has been developed by bromination of azulene in aqueous tetrahydrofuran. Reduction of 3-bromo-1,5- and ?1,7-azulenequinones with tin or zinc powder in acetic acid gave the parent 1,5- and 1,7-azulenequinones, and further reduction products. 相似文献