邻氯苯乙烯-二乙烯基苯强酸性阳离子交换树脂的合成工艺

以邻氯苯乙烯和二乙烯基苯为原料制备了邻氯苯乙烯-二乙烯基苯强酸性阳离子交换树脂,考察了水油比、分散剂、助分散剂等因素对合成树脂的影响。研究表明,该树脂的合成最佳工艺条件为:水油比3:1~4:1,聚乙烯醇与明胶分别为水相质量的0.1%和1.0%,助分散剂为水相质量的0.5%,电解质为水相质量的10%,在40~80℃的成球关键期控制升温速率为20℃/h,在80~110℃以发烟硫酸辅助磺化,得到交换量大于4mmol/g的树脂,优化了该树脂的合成工艺。     

对氟苯乙烯-二乙烯基苯强酸性阳离子交换树脂的合成及其热稳定性研究

以对氟苯乙烯，二乙烯苯为原料合成了强酸性阳离子交换树脂，考察了磺化反应的工艺条件及卤原子，树脂类型对树脂耐热稳定性能的影响。研究表明，对氟苯乙烯－二乙烯基苯共聚体需用发烟硫酸在110℃才可磺化，大孔磺化对氟苯乙烯－二乙烯基苯树脂在190℃水中20h的磺酸基降解率为24．7％，而普通磺酸树脂的磺酸基降解率为53．3％。     

浓环氧乙烷水溶液的选择性催化制乙二醇工艺研究

合成了苯乙烯型强碱阴离子交换树脂,将其用于环氧乙烷催化水合制乙二醇反应中,研究了温度、浓度、空速对树脂催化性能的影响,探讨了树脂的不可逆膨胀及失活原因.结果表明,在393K树脂发生降解,降解物与环氧乙烷反应生成聚乙二醇胺,导致树脂膨胀破裂;在温度353K,压力1.5MPa,液时空速0.2h-1下,环氧乙烷转化率100%,乙二醇的选择性96.3%,使用1600h后,催化剂的膨胀率6%,强碱容量损失率7.5%.     

聚(邻氯苯乙烯-二乙烯基苯)强酸性阳离子交换树脂催化丁烯水合工艺

采用聚(邻氯苯乙烯-二乙烯基苯)强酸性阳离子交换树脂间歇催化丁烯水合反应,考察了水烯比、反应时间、反应温度、反应压力等因素对仲丁醇收率的影响,并用STATISTIC统计软件对实验计算优化,得到最佳工艺条件为:水烯比4.4、反应时间8.2h、催化剂用量占反应物总量的4.7%、反应压力5.5MPa、反应温度169℃,仲丁醇的计算收率为6.91%,与验证实验的结果基本一致。     

耐高温强碱性阴离子交换树脂催化剂的合成及应用

以大孔苯乙烯-二乙烯基苯共聚白球和1,3-噁嗪-2-酮为原料,烷基化、叔胺化和季铵化后得含有长碳链间隔臂的强碱阴离子交换树脂催化剂.用IR、EDS、HR/MAS表征了树脂的结构,测定了热稳定性和催化环氧乙烷水合的性能.OH-型树脂在100℃去离子水中720 h交换量下降率为11.8%.HCO3-型树脂在90℃、1.8 MPa、空速0.17 h-1,水与环氧乙烷比6.4的条件下,催化EO水合转化率98%,MEG选择性95%,200 h后交换量下降率小于2%.     

碱性燃料电池用PFA基季铵盐类阴离子交换膜的稳定性

采用辐射接枝法将氯甲基苯乙烯（VBC）接枝到四氟乙烯-全氟烷氧基乙烯基醚共聚物（PFA）基底上并对其进行季铵化和碱性化改性制备了阴离子交换膜（PFA-g-PVBC）.对制得的膜采用薄膜拉伸试验、热重（TG）、热水和热碱处理等方法考察了其机械性能、热稳定性和化学稳定性.结果表明：PFA-g-PVBC阴离子交换膜具有良好的机械性能,该膜在60℃去离子水中和室温下碱性溶液中可稳定存在,但在60℃碱性溶液中因Hofmann降解反应和直接亲核取代反应而导致其电导率下降.将该膜应用于常温＂自呼吸＂式碱性直接乙醇燃料电池中,30mAcm-2恒电流放电情况下,电池可一次性连续放电10h以上,累计放电时间长达30h.     

新型酰乙基葡甲胺树脂的合成及吸硼性能

采用一步法, 用氯乙酰化聚苯乙烯树脂(PS-Acyl-Cl)与葡甲胺反应制得一种同时含有α-酰乙基胺和邻羟基双官能团的新型酰乙基葡甲胺树脂, 考察了溶液pH值、 温度、 初始浓度和吸附时间对酰乙基葡甲胺树脂吸附硼的影响. 结果表明, 在实验浓度范围内, 该树脂对硼的吸附符合Langmuir方程, 最大吸附量约为28.1 mg/g干树脂, 优于氯甲基树脂制得的硼特效树脂. 表明α-酰乙基胺和邻羟基双官能团对硼有双重或协同吸附作用. 该树脂在pH=6.0时对硼的吸附量最大; 温度对树脂吸附的影响不大; 树脂解吸率大于96%; 树脂重复使用5次后吸附量基本不变. 动力学研究结果表明, 吸附过程为液膜扩散控制过程.     

含长碳链间隔臂结构的强碱性阴离子交换树脂的合成及热稳定性

研究了一种含长碳链间隔臂结构的强碱性阴离子交换树脂的新合成方法.评价了该树脂在水中的热稳定性.结果表明,以苯乙烯-二乙烯基苯共聚白球和1,3-噁嗪-2-酮为原料,季铵型离子液体为催化剂,得到带有胺丙基的苯乙烯-二乙烯基苯共聚珠体,再用甲酸和甲醛N-甲基化,溴乙烷季铵化,可以生成强碱交换量为1.86mmol/g强碱阴离子交换树脂.含长碳链间隔臂结构的OH~-型阴离子交换树脂在100℃去离子水中保持720h交换量仅下降11.83%,好于商业通用的强碱阴离子交换树脂.     

对氯甲基苯乙烯与丙烯腈、甲基丙烯酸酯类的自由基共聚研究

<正> 对氯甲基苯乙烯(p-CMS)是合成功能高分子的一个非常有用的起始单体,利用它的均聚以及与其它烯类单体的共聚反应,可制得含活性基团的高分子材料。但以往对该单体的聚合及共聚研究,较多的是以邻、间、对位氯甲基取代苯乙烯的混合物作为研究对象。本文采用纯对氯甲基苯乙烯,在开展对其基本性质、均聚反应机理研究的同     

酸性吸附树脂对水中邻氨基苯甲酸甲酯的吸附性能研究

在氯甲基化的苯乙烯-二乙烯苯聚合物的基体上,经后交联反应并分别用阿特拉津、氨基磺酸、偏苯三甲酸酐和浓硫酸物质加以修饰,以期得到既具有高比表面积又具有适量交换基团的吸附树脂。研究了邻氨基苯甲酸甲酯在5种吸附树脂上的静态吸附及动态吸附行为,并研究了FJ-1树脂的脱附行为。结果表明,化学修饰的吸附树脂对邻氨基苯甲酸甲酯的较优吸附温度为303K,具有丰富羧基基团修饰和合适孔径的吸附树脂对邻氨基苯甲酸甲酯有更好的吸附效果。FJ-1吸附树脂对邻氨基苯甲酸甲酯的动态吸附效果最好,该树脂吸附邻氨基苯甲酸甲酯后,易于脱附。用甲醇作为脱附剂,在温度333K,脱附流速0.5BV/h条件下,脱附率为75%。     

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.