二茂铁金属有机液晶的合成,结构及介晶性研究

我们曾研究了以季铵盐作为相转移催化剂,通过二茂铁的芳基化反应,合成了一系列带活泼官能团的二茂铁衍生物［１］。这些衍生物可作为合成二茂铁非线性光学材料、液晶材料的良好中间体［２－４］。为了探索分子几何结构与介晶性能之间的关系和制备结构新颖、稳定性能好、...     

新型双膦配体及钯催化的烯丙基烷基化反应用于构筑季碳手 性中心

从二茂铁恶唑啉膦化合物(Sp)-1出发,合成了严平面手性二茂铁修饰的口袋型双膦配体(R,R,Sp,Sp)-4和(S,S,Sp,Sp)-4。这类配体在前手性亲核试剂的不对称烯丙基化构筑手性季碳中心的反应中,显示了较好的反应活性及对映选择性。当利用亚胺的氨基酸酯衍生物时,可以得到一些非天然的季碳氨基酸衍生物,ee值最高可以达到75.3%。一些简单的酮的烯醇负离子也可用作亲核试剂,产物为α-位双取代的具有季碳中心的酮,ee值可高达95%。     

新型二茂铁甲基季铵盐离子液体的合成与表征

以二茂铁与二甲胺为原料合成了碘化二茂铁甲基季铵盐,再经复分解反应得到乙酸二茂铁甲基季铵盐离子液体;表征了离子液体的结构,测定了其熔点和溶解性.结果表明,合成的乙酸二茂铁甲基季铵盐离子化合物熔点低于100℃,是一种新型的二茂铁甲基季铵盐离子液体.     

金属锡促进下含氮芳杂环化合物的选择性烯丙基化反应

本文报道了金属锡粉促进下含氮芳杂环的烯丙基化反应。在氯甲酸酯存在下, 利用烯丙基溴和金属锡原位生成的烯丙基锡试剂作为亲核试剂捕捉体系中的N-酰化季铵盐, 合成了一系列烯丙基取代N-酰基杂环衍生物。反应对于咪唑, 噻唑, 吡啶, 嘧啶等含氮含硫的杂环都适用, 并且对于巴豆基溴的反应表现出良好的区域选择性。     

组合化学法筛选聚苯乙烯固载季铵盐相转移催化剂研究(I)

利用组合化学方法合成了一个含有60种不同结构的聚苯乙烯固载季铵盐相转移催化剂的催化剂库,以有外加碱条件下亲核取代反应为探针反应,利用迭代法从中筛选出了活性最高的催化剂,建立了一种快速合成和筛选聚苯乙烯固载季铵盐相转移催化剂的方法。     

吡啶季铵盐在有机合成中的应用

由于吡啶环的芳香性、碱性、吡啶氮原子的吸电子效应使得吡啶季铵盐具有丰富的化学反应性质, 可以进行亲核加成、Michael加成、1,3-偶极加成、亲核取代和σ-迁移重排等反应, 在有机合成化学中有广泛的应用.     

相转移催化在高分子化合物合成中的应用

 综述了相转移催化用于高分子化合物合成的主要研究进展．介绍了季铵盐类及冠醚类相转移催化剂在高聚物的亲核取代反应、阴离子开环聚合反应及自由基聚合反应中的应用．重点总结了亲核取代反应中聚苯乙烯类化合物的功能化及化学修饰，包括合成路线、反应机理、温度以及催化剂和溶剂的种类与用量等因素对反应的影响．冠醚类化合物的催化效果略优于季铵盐类化合物，而后者的成本低、毒性小、应用更广泛，其催化的反应应作为今后研究的重点，以期将相转移催化技术尽早用于工业化生产．     

有机/无机杂化材料担载季铵盐催化剂的制备及其在相转移催化反应中的应用

利用溶胶-凝胶(S0l-gel)技术制备了新型的有机／无机杂化材料担载的季铵盐催化剂。优化了制备方法、反应条件等多种因素；考察了其作为相转移催化剂在1-溴代正庚烷与碘化钾的亲核取代反应中的应用，转化率最高可达到95％。     

二茂铁氮丙啶衍生物的合成与性质

由二茂铁羧酸酰氯和氮丙啶通过亲核取代反应,合成了二十四种新的二茂铁氮丙啶化合物,并做了元素分析和红外、核磁波谱的测定。     

含二茂铁核的硅有机衍生物的合成

合成了一系列含二茂铁核的硅有机衍生物.试图从环戊二烯基三甲基硅烷与FeCl₂在二乙胺存在下制取1,1'-双(三甲基硅烷基)二茂铁,由于Si-C键的断裂,未获预期产物而得二茂铁. 为了合成双有机硅基二茂铁,采用了两种方法.方法之一是从1,1'-二茂铁二钠与相应的三烷基氯硅烷反应制得1,1'-双(三甲基硅烷基)二茂铁、1,1'-双(三丁基硅烷基)二茂铁和1,1'-双(二甲基苯基硅烷基)二茂铁.为了取得单取代硅烷基二茂铁,采用二茂铁锂,但一般得单和双取代衍生物的混合物,它们很难分离;如减少有机氯硅烷用量,则可得纯的单取代乙烯基二乙基硅烷基二茂铁.另一方法是将三甲基-γ-氯丙基硅烷的格氏试剂与二乙酰基二茂铁反应制得含二茂铁核的双叔醇.     

The Synthesis and Characterization of Aryloxy-Linear Phosphazenes

The reactions of N-dichlorophosphoryl-P-trichloromonophosphazene with sodium o-methylphenoxide, sodium p-methylphenoxide, sodium f -naphthalenoxide, monosodium 4-(2-pyridylazo)resorcinol, and sodium 1-nitroso-2-naphthaleneoxide have been investigated. Experimental studies were carried out in argon atmosphere. The sodium aryloxides were prepared from naphthalene or phenol derivatives and metallic sodium. The phosphazene and phenolate or naphthaleneoxide were reacted at 0°;C and then refluxed. After the reaction products were separated by using column chromatography, the structures of the compounds were defined by elemental analysis, IR, 1 H, 13 C, 31 P NMR, and mass spectroscopy. Tetra- and pentasubstituted monophosphazenes were obtained from sodium o-methylphenoxide. Pentasubstituted derivatives also were obtained from sodium p-methylphenoxide and sodium f -naphthaleneoxide. Phosphazene or any phosphorus compound could not be isolated from the reaction of phosphazene with monosodium 4-(2-pyridylazo)resorcinol and sodium 1-nitroso-2-naphthaleneoxide.     

二氧化碳和水气氛对高钠煤转化过程中钠迁移的影响

对新疆的两种高钠煤（伊犁煤YL、呼图壁煤HTB）进行了N₂、CO₂和H₂O气氛和不同温度下钠迁移的研究。采用逐级萃取和湿法消解法确定了原煤、半焦中钠的赋存形态,定量研究了两种煤中钠的挥发及迁移规律。结果表明,YL煤的形态钠中水溶钠占80.08%,HTB煤的形态钠中不溶钠占61.54%。不同气氛下,升高温度都可促进两种煤中钠的挥发,半焦中水溶钠比例减小,醋酸铵可溶钠比例会出现先增加后减少现象,盐酸可溶钠比例呈增加趋势。对于YL煤,CO₂气氛可抑制钠的挥发,H₂O蒸气可促进钠的挥发;900℃时,YL煤CO₂气氛下钠挥发仅为N₂气氛下的50.25%,而H₂O气氛钠挥发为N₂气氛下的111.45%。对于HTB煤,CO₂气氛也可抑制钠的挥发,900℃时CO₂气氛下钠挥发为N₂气氛的80.91%;HTB煤在H₂O蒸气下,800℃之前钠挥发高于N₂,当900℃时,钠挥发略低于N₂气氛。YL煤形态钠中以水溶钠为主,其挥发的同时会向盐酸可溶钠及不溶钠转变。而HTB煤形态钠中以不溶钠为主,其次是水溶钠,CO₂和H₂O气氛能促进不溶钠向其他可溶态钠转变。     

聚丙烯酸钠在Al2O3/水界面吸附行为的ESR研究

采用电子自旋共振技术结合自旋标记方法研究了聚丙烯酸钠在Al2O3／水界面吸附的分子构型和运动行为。结果表明，哌啶氮氧自由基在聚丙烯酸钠分子上是链间标记，它的运动受到聚合物长链的束缚；聚丙烯酸钠在Al2O3上的吸附等温线呈Langmuir型，随表面吸附量的增加，吸附在Al2O3上的聚丙烯酸钠分子的固着链节分数减小，从平衡浓度0.25mg/ml时的0．90变化到饱和吸附时的0．65。聚丙烯酸负离子通过静电引力多点吸附在Al2O3表面，分子中的大部分链节平躺在Al2O3表面，少部分链节伸向溶液。     

Solid-liquid Metastable Equilibria in Quaternary System （NaCl＋Na2CO3＋Na2SO4＋H2O） at 273.15 K

The metastable phase equilibria of the quaternary system NaCl+Na2CO3+Na2SO4+H2O were studied at 273.15 K. The salts' solubilities, densities and pH values of the equilibrated solution in this system were determined. According to the experimental data, the metastable equilibrium phase diagram, the diagram of density vs. composition and pH vs. composition diagram were plotted. The phase diagram consists of five univariant curves, four crystallization fields and two invariant points. The four crystallization fields correspond to sodium carbonate decahydrate (Na2CO3·10H2O), sodium sulfate decahydrate(Na2SO4·10H2O), sodium chloride(NaCl) and burkeite(2Na2SO4· Na2CO3), respectively. The crystallization field of sodium sulfate decahydrate(Na2SO4·10H2O) is the largest, which indicates that sodium sulfate is easy to saturate and crystallize from solution at 273.15 K.     

三取代直链烷基苯磺酸钠的界面扩张性质

利用悬挂滴方法研究了五种表面活性剂3,4-二己基苯磺酸钠(66)、3,4-二庚基苯磺酸钠(77)、2-乙基-4,5-二己基苯磺酸钠(266)、2-丙基-4,5-二己基苯磺酸钠(366)和2-丁基-4,5-二己基苯磺酸钠(466)在空气-水和癸烷-水界面上的扩张流变性质,考察了烷基取代在苯环不同位置对分子界面行为的影响.研究发现,苯环不同位置的取代烷基链长变化对扩张弹性模量和扩张粘性模量影响不同.随着烷基链长增长,表面扩张弹性模量均增加,而扩张粘性模量表现则不同:邻位短链烷基碳数从2变化到4,对粘性模量贡献不大;而间位长链烷基增长对表面弛豫过程影响较大,粘性模量明显增大.油分子的插入能大大削弱间位长链烷基间的强相互作用,一方面导致界面弹性模量和粘性模量远低于表面,同时使得同分异构分子77和266的界面扩张粘性模量数值接近.     

铝酸钠溶液的鲁米诺增强声致发光研究

Ultrasonic processing on sodium aluminate solutions was proved to have effects on the gibbsite crystallization process from sodium aluminate solution. In order to investigate the mechanism of the ultrasonic intensification, the sonofluorescence spectrum was detected by fluorescence spectrometer in sodium alumiante Luminol solutions, and the spectrum under the conditions of various ultrasonic power and different composition of sodium aluminate solutions were studied. It is found that the sodium aluminate Luminol solution can irradiate fluorescence by ultrasonic processing above the given power; the intensity of sonofluorescence are relatively low in sodium aluminate solutions with high concentration and low αk（mol ratio of Na2O/Al2O3 in sodium aluminate solution）. The relationship between the sonofluorenscence and ultrasonic intensification on gibbsite crystallization process from sodium aluminate solutions were also discussed. The conclusion that the ultrasonic effects are influenced by ultrasonic cavitation and intensity of sonofluorescence spectrum is deduced.     

钠对苯甲醛加氢合成苯甲醇催化剂Cu/SiO2的修饰作用影响活性

采用浸渍法引入不同含量的钠元素对Cu/SiO₂催化剂进行了改性, 并对苯甲醛加氢合成无氯苯甲醇反应进行了研究. XRD, H₂-TPR, BET, IR等表征分析结果表明: 经钠元素修饰后的催化剂并没有改变CuO的晶相结构, 但增强了活性组分和载体间的相互作用, 使CuO的还原温度得到提高; 催化剂表面的酸量和酸强度随钠元素修饰量的增加而显著降低; 钠的最佳负载量为1.0% (w), Na-Cu/SiO₂催化剂能够有效抑制副产物甲苯的生成, 显著地提高产物苯甲醇的高温选择性.     

Determination of carbon in solidified sodium coolant using new ICP-OES methods

New methods for the determination of carbon in sodium using laser ablation inductively coupled plasma optical emission spectrometry (LA-ICP-OES) and ICP-OES with pneumatic nebulisation (PN-ICP-OES) were developed. The determination was required for the study of the carbon dioxide reaction with molten sodium at high temperatures (300–600°C). After exposition to CO₂, the solidified sodium sample was subjected to direct solid analysis by LA-ICP-OES and to solution analysis. For the determination of carbon in the sodium sample surface layer by LA-ICP-OES, three different matrices containing sodium were tested (NaCl, NaF, and Na₂B₄O₇ · 10H₂O) as calibration pellets. The calibration dependences were improved using sodium as the internal standard. Average carbon content in the sodium bulk sample was determined by PN-ICP-OES after the sample dissolution by water vapour.     

双甲基化大豆苷元磺酸盐的合成、晶体结构及活性研究

以大豆苷元为原料合成了强水溶性异黄酮类化合物7,4′-二甲氧基异黄酮-3′-磺酸钠(1)和7,4′-二甲氧基异黄酮-3′-磺酸铜(2).X射线单晶衍射分析表明,化合物1的分子组成为[Na(H₂O)₂](C₁₇H₁₃O₄SO₃),Na的配位数为6,且相邻钠离子以7,4′-二甲氧基异黄酮-3′-磺酸根氧原子桥连,与两个磺酸根的3个氧原子和1个S原子组成六元环,六元环通过Na-O配位键彼此稠合,在晶体结构中形成延伸的锯齿状聚合八面体配位钠离子链;这些钠离子链之间又通过配位水与配位水、磺酸根之间的氢键作用自组装成二维结构的超分子离子聚合物.化合物2的分子组成为[Cu(H₂O)₆](C₁₇H₁₃O₄SO₃)₂·8H₂O,Cu(Ⅱ)位于对称中心上.[Cu(H₂O)₆]²⁺,C₁₇H₁₃O₄SO^-₃和H₂O之间存在多种氢键;并且异黄酮环反平行排列存在π…π的堆积作用.氢键和π…π的堆积作用使化合物2自组装成三维结构的超分子.抗缺氧缺血活性试验结果表明,它们的抗缺氧缺血活性比大豆苷元的高.     

Effect of sodium citrate on preparation of nano-sized cobalt particles by organic colloidal process

Nano-sized cobalt particles with the diameter of 2 nm were prepared via an organic colloidal process with sodium formate, ethylene glycol and sodium citrate as the reducing agent, the solvent and the complexing agent, respectively. The effects of sodium citrate on the yield, crystal structure, particle size and size distribution of the prepared nano-sized cobalt particles were then investigated. The results show that the average particle diameter decreases from 200 nm to 2 nm when the molar ratio of sodium citrate to cobalt chloride changes from 0 to 6. Furthermore, sodium citrate plays a crucial role in the controlling of size distribution of the nano-sized particles. The size distribution of the particle without sodium citrate addition is in range from tens of nanometers to 300 or 400 nm, while that with sodium citrate addition is limited in the range of (2±0.25) nm. Moreover, it is found that the addition of sodium citrate as a complex agent could decrease the yield of the nano-sized cobalt particle. __________ Translated from Journal of South China University of Technology, 2008, 36(3) (in Chinese)