含有离子交换基的冠醚共缩聚物的合成与性能

本工作采用对磺酸基(羧酸基)苯酚与甲醛反应生成的2,6—二羟甲基—4—磺酸基(羧酸基)本酚二钠盐与单苯并冠醚、二苯并冠醚缩聚,合威了两个不同系列高度水浸润性冠醚聚合物;测定了它们的溶胀性、热稳定性和络合性能。这类新型冠醚聚合物的络合能力显著优于相应冠醚聚合物,其中P_sBl5C5动态络合容量(Ag~+)最高:1.3mmol/g。     

生色冠醚研究

用４－甲基－７－羟基－８－甲酰基香豆素与三种４′－氨基苯并冠醚和４′，４″－二氨基二苯并－１８－冠－６反应，合成了四个新的Ｓｃｈｉｆ碱型苯并冠醚。它们都是有色化合物，具有强荧光性质。在这些Ｓｃｈｉｆ碱型苯并冠醚溶液中加入过渡金属盐时，不同程度地发生荧光猝灭现象，生成的配合物也是荧光化合物；而加入碱金属和碱土金属盐时，则荧光性质几乎不受影响     

冠醚共缩聚物的合成与性能（Ⅱ）

采用２，６－二羟甲基苯酚类化合物分别与单苯并冠醚（Ｂ１５Ｃ５、Ｂ１８Ｃ６）和二苯并冠醚（２Ｂ１８Ｃ６、２Ｂ２４Ｃ８、２Ｂ３０Ｃ１０）在酸催化下缩聚，合成了不同两个系列冠醚共缩聚物，这些聚合物Ｍ＝１２００－４５００，可溶于氯仿等溶剂，萃取性能和络合选择性均有所提高。作为树脂使用，动态吸附容量为０．０５－０．１５ｍｍｏｌ／ｇ，并有较好的色谱特性。     

冠醚共缩聚物的合成与性能

双冠醚化合物对某些金属离子比单冠醚具有更好的络合性能和选择性,它们合成、应用研究越来越受到人们的重视,本工作采用2,6-二羟甲基对甲氧基苯酚为缩合剂与芳香族冠醚缩聚,得到一系列具有双冠醚结构特征的新酚醛型聚苯并冠醚(简称聚冠醚),聚冠醚合成容易,并呈现了比相应单冠醚更优越的络合萃取能力和富集效率。     

冠醚共缩聚物的合成与性能（Ⅱ）

采用２，６－二羟甲基苯酚类化合物分别与单苯并冠醚（Ｂ１５ＣＳ、Ｂ１８Ｃ６）和Ｍ苯并冠醚（２Ｂ１８Ｃ６、２Ｂ２４Ｃ８、２Ｂ３０Ｃ１０）在酸催化下缩聚，合成了两个系列冠醚共缩聚物．这些聚合物Ｍ＝１２００—４５００，可溶于氯仿等溶剂，萃取性能和络合选择性均有所提高．作为树脂使用，动态吸附容量为０．０５—０．１５ｍｍｏｌ／ｇ，并有较好的色谱特性．     

基于密度泛函理论研究锂-冠醚复合物的结构和热力学参数

冠醚对碱金属离子具有高选择性,在锂元素的分离富集上有着广泛的应用。本文基于密度泛函理论（DFT）研究了冠醚环大小、取代基种类、配位原子种类和数量等因素对冠醚空间结构和热力学参数的影响。结果表明,苯并冠醚系列中的苯并-15-冠-5具有更好的配位能力,取代基、配位原子对冠醚的络合能力均有一定影响,因此可通过选择合适的冠醚环,引入供电子基团和含氮杂原子等方法来改善冠醚的分离富集能力。这对冠醚体系分离富集锂元素具有重要的指导意义。     

冠醚化合物的合成(ⅩⅠⅩ)——双羟基冠醚衍生物的合成

本文用3,5-二叔丁基二苯并-14-冠-4双羟基冠醚的顺式和反式异构体分别与溴乙酸、3-溴丙酸及氯代乙酰氯反应,制备了4个双羧酸冠醚及2个双氯代乙酸酯冠醚衍生物。此外,通过1,1′-(邻苯)-双-(2,3-环氧丙基)醚与2,2′-联苯二酚反应,合成了联苯型苯并14-冠-4双羟基冠醚,分离了顺、反异构体,并使之与溴乙酸反应,制备了相应的双羧酸冠醚衍生物。10个新化合物的结构均经IR、¹H NMR、MS和元素分析确定。     

高分子冠醚的离子结合性质及其应用——(Ⅳ)用苯并-15-冠-5甲醛聚合物分离富集原子吸收法测定大量锌中的镉

近年来,在分析化学领域内已开展了冠醚的应用研究工作。同时,兼具离子交换树脂性能的高分子冠醚作为选择性吸附分离剂也引起了分析工作者的注意。Blasius等人合成了多种高分子冠醚并用于元素的分离和分析。我们也进行过这方面的研究工作。本文将报导以苯并-15-冠-5甲醛聚合物为固定相,在几种介质中吸附锌和镉。结果表明,在碘化钾中镉的吸附达100％,而锌不被吸附。用聚合物在该介质中分离富集,原子吸收法测定锌和镉效果令人满意。使用的苯并-15-冠-5甲醛聚合物结构为:     

冠醚化合物的合成(Ⅲ)——饱和漆酚冠醚的合成及其异构体分离

本文采用我国生漆为起始原料,经催化氢化与缩合反应,合成了五种长链烷基取代的二苯并冠醚即饱和漆酚冠醚,并使用分步结晶法和薄板层析法对其顺反异构体进行了分离。     

新的酚型开链冠醚及由其衍生的二苯并冠醚的合成

将水杨醛与碱和氯甲基甲基醚反应, 再经过NaBH4还原, 即制得邻(甲氧基甲氧基)苯甲醇, 然后将其在DMF中与NaH和二(或三)甘醇二对甲苯磺酸酯反应, 得开链冠醚1a和1b。1a和1b经稀酸水解, 即脱保护而分别生成新的酚型开链冠醚2a和2b。用2a与二甘醇二对甲苯磺酸酯和NaH在DMF溶液中反应, 合成顺型二苯并-20-冠-6(3); 而2a与环氧氯丙烷在NaOH水溶液中反应, 则合成了17-羟基二苯并-18-冠-5(4)。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

关于"对‘燃料电池物理及化学性能的有限时间热力学分析方法'的讨论”答复

把有限时间热力学理论用于化学过程的研究,将会得到一系列新的结论,开展这方面的研究是很有意义的.文献[1]以燃料电池为例,在同时考虑化学反应及传热不可逆性的情况下,研究了燃料电池的性能界限,文献[2]指出了文献[1]计算化学反应及传热不可逆性而引起系统与有关环境的总熵产生率的错误以及由此而导致的结论所存在的问题,并进行了富有启发性的分析与讨论.但文献[2]对于系统与有关环境的总熵产生率的计算也是不正确的,由此得到的其它结论自然不能成立.本文将就此情况下系统与有关环境的总熵产生率的计算再次进行讨论,并给出电池功率和效率的有限时间热力学性能界限.