芳香族二腈的聚合

合成了三氯化硼、三氯化铝、四氯化钛、三氯化铁、氯化锌、氯化钴、四氯化锡、五氯化锑等八种氯化物和联苯二甲腈的分子复合物。它们具有一定的分子组成、熔点、 色泽、极易吸水分解。测定了它们的红外光谱,得到复合后氰基伸展振动频率的增加值及吸收峰强度增加值。这些复合物对联苯二甲腈的聚合有不同程度的催化能力。实验证明Lewis酸作为芳香族二腈聚合的催化剂是通过的腈生成复合物的形式进行催化的。     

中孔载体上组装Ti催化活性中心的研究Ⅰ-钛配合物在中孔HMS载体上的组装

利用六角中孔硅载体（记为 HMS）上丰富的表面羟基与钛酸异丙酯、四氯化钛的交换反应,实现了钛配合物在载体上的组装。 FT-IR表征表明载体与钛化合物的键合作用会使样品出现一个新的 960cm－ 1带, 该带可归属于与钛化合物键合的 Si-OH振动带;交换温度会明显影响钛化合物与载体羟基的交换反应模式;酒石酸二乙酯（ DET）被键合后其 C=O带没有明显位移证明 DET是以其 OH与键合在载体上的钛化合物发生键合作用。在催化苯乙烯环氧化反应中,键合于载体上的钛配合物比其均相配合物的催化活性要高得多,钛源、配体和交换温度对催化氧化活性和环氧化选择性均有较大影响。     

中孔载体上组装Ti催化活性中心的研究Ⅰ—钛配合物在中孔HMS载体上的组装

利用六角中孔硅载体（记为ＨＭＳ）上丰富的表面羟基与钛酸异丙酯、四氯化钛的交换反应,实现了钛配合物在载体上的组装。ＦＴ－ＩＲ表征表明载体与钛化合物的键合作用会使样品出现一个新的９６０ｃｍ＾－１带,该带可归属于与钛化合物键合的Ｓｉ－ＯＨ振动带;交换温度会明显影响钛化合物与载体羟基的交换反应模式;酒石酸二乙酯（ＤＥＴ）被键合后其Ｃ＝０带没有明显位移证明ＤＥＴ是以其ＯＨ与键合在载体上的钛化合物发生键合作用     

镁-钛系聚乙烯高效催化剂的机理研究

本文对一种典型的反应法制聚乙烯高效催化剂的各步反应产物进行了研完:第一步氯化镁加乙醇反应,生成醇合物MgCl₂·nC₂H₅OH,其作用是将氯化镁晶格破坏;第二步加烷基铝,第三步加四氯化钛,其作用是与醇合物中的醇反应使之溶解,重新生成高分散的氯化镁微晶,活性组份钛化合物高度分散在氯化镁微晶表面上,故催化剂具有高活性。用这种反应法制得的高效催化剂,载体分散度高,内部孔隙多,有利于传质,因而比一般研磨法制得的高效催化剂聚合收率高。X光衍射发现在其他一些聚乙烯高效催化剂中也存在微晶MgCl₂,说明它们的高活性机理是类似的。     

三氯化铝烷基氯化咪唑盐结构和红外光谱的模拟计算

采用量子化学密度泛函的方法计算了三氯化铝烷基氯化咪唑盐的红外光谱, 预测了三氯化铝烷基氯化咪唑盐的分子结构和光谱. 合成了三氯化铝1-丁基-3-甲基-咪唑盐[(BMIM)AlCl4], 并测试了其红外光谱, 对预测的分子结构和红外光谱进行了验证.     

α-卤代酮和羰基化合物在碘化钾/金属盐作用下的碳-碳双键形成反应

本工作研究了α-卤代酮与羰基化合物之间在易得试剂碘化钾和某些硬路易斯酸的金属盐, 如三氯化铝, 四氯化钛等复合作用下形成碳碳双键, 生成(E)-α,β-不饱和羰基化合物的反应。     

中孔载体上组装Ti催化活性中心的研究Ⅲ. 中孔分子筛与钛化合物键合作用的红外光谱表征

FT-IR表征了中孔分子筛(HMS)载体与钛酸异丙酯、四氯化钛、酒石酸的键合作用, 这种键合作用均会诱导载体的硅氧四面体发生弱的畸变, 而在960 cm-1附近出现吸收谱带.键合温度、溶剂以及钛源均会影响谱带的位置和强度.测得的钛负载量与该谱带强度成正比.催化苯乙烯环氧化结果表明, 键合温度、钛源、钛中心配位环境对键合催化剂的活性和环氧化选择性均有较大的影响.     

络合滴定法同时测定氯化熔盐中氯化亚铁和氯化铁的含量

<正>氯化熔盐是高钛渣、氯气、焦炭等原料在反应炉内经高温加热反应的产物,此高温加热反应是氯化法生产四氯化钛的核心工艺[1]。根据高钛渣的成分,氯化熔盐中主要有氯化钠、氯化钙、氯化镁、氯化铁、氯化亚铁以及未反应的二氧化钛和二氧化硅[2-3]。氯化熔盐不仅是氧化物、氯化物的介质,还是提高反应区氯化物含量的有效催化剂,三价铁的存在,可使二氧化钛的氯化速率提高好几倍,因为三     

中孔载体上组装Ti催化活性中心的研究：Ⅲ.中孔分子筛与钛化合物键 …

ＦＴ－ＩＲ表征了中孔分子筛（ＨＭＳ）载体与钛酸异丙酯,四氯化钛、酒石酸的键合作用,这种键合作用均会诱导载体的硅氧四面体发生弱的畸变,而在９６０ｃｍ＾－１附近出现吸收谱带,键合温度、溶剂以及钛源均会影响谱带的位置和强度。是的钛负载量与该谱带强度成正比。催化苯乙烯环氧化结果表明,键合温度、钛源、钛中心配位环境对键合催人 和环氧化选择性均有较大的影响。     

钛醇盐电化学合成的研究

采用钛金属为“牺牲”阳极,首次在无隔膜电解槽中,电化学一步法制备了纳米TiO~2前驱体钛醇盐Ti(OEt)~4,Ti(OPr-i)~4,Ti(OBu)~4。产物通过元素分析、红外光谱(FT-IR)、拉曼光谱进行表征。电化学一步法直接制备纳米材料前驱体钛醇盐,克服了传统化学方法合成金属醇盐步骤多、产率低、纯度达不到要求及后续分离繁琐等缺点。本文同时讨论了影响电合成钛醇盐的关键因素及可能的反应机理,实验表明钛在醇溶液中呈点蚀行为,钛醇盐卤化物Ti(Ⅲ)(OR)~nBr~m在阳极形成,然后被氧化为Ti(Ⅳ)(OR)~nBr~m,这种物质在阴极上ROH参与下被还原生成钛醇盐Ti(OR)~4,钛阳极表面拉曼光谱证实了上述观点。防止阳极钝化,温度控制在50～60℃之间,彩有机胺溴化物为导电盐,可以提高电合成收率。     

Electron spin resonance studies on Ziegler-Natta type catalyst systems

Electron spin resonance spectra of Ziegler-Natta type catalyst systems (titanium trichloride and alkyl aluminums) have been studied. When triethylaluminum was added to titanium trichloride, an absorption with a g value of 1.96 was observed from the solid phase of the system. The number of spins of this signal is equal to that of the active centers for propylene polymerization. The solid phase from the mixture of titanium trichloride and diethylaluminum chloride also gives the same signal, which suggests the identity of the action of two alkyl aluminums on titanium trichloride surface. The signals obtained from the liquid phase of the both systems are all ascribed to the reaction products of the reaction of alkyl aluminum with titanium tetrachloride occluded in solid.     

2-吲哚酮和5-甲基-2-吲哚酮的无溶剂法制备

以苯胺和氯乙酰氯为原料在NaOH存在下酰化合成N-氯乙酰基苯胺,然后N-氯乙酰基苯胺在无水AICI,催化下环化合成2-吲哚酮．对由N-氯乙酰基苯胺合成2-吲哚酮的工艺条件进行了改进．结果表明合成2-吲哚酮的最佳条件为：反应温度为220℃,反应时间为60min,加料时温度为180℃,N-氯乙酰基苯胺与氯化钠,无水AlCl3的重量比为1：1：5．5．改进后的合成2-吲哚酮收率达到88．3％,纯度99％,收率比原工艺提高了24．6％．在此基础上,还合成了5-甲基-2-吲哚酮,并得到其最佳条件为：反应温度为190℃,反应时间为30min,加料时温度为180℃,4-甲基-N-氯乙酰基苯胺与氯化钠,无水AlCl3的重量比为1：1：5．5,收率达到83．1％,纯度为99％．     

Quantification of pharmaceutical polymorphs and prediction of dissolution rate using theophylline tablet by terahertz spectroscopy

Theophylline has an anhydrous form and a monohydrated form, and the dissolution rate of the anhydrous form is higher than that of the monohydrated form. Terahertz (THz) spectra of theophylline tablet containing the theophylline anhydrous form, monohydrated form, microcrystalline cellulose and magnesium stearate exhibited a specific absorption peak at 0.96 THz, where the theophylline anhydrous form demonstrated an absorption peak. Additionally, the intensity of the peak at 0.96 THz gradually decreased as the proportion of the anhydrous form decreased. The multivariate data analysis was performed to correlate the THz spectra of theophylline tablets with the ratio of the theophylline anhydrous form. The calibration model used to predict the mixing ratio of the theophylline anhydrous form from the THz spectra achieved root-mean-squared errors of cross-validation (RMSECV) of 2.89%, a slope of 0.9934 and an R(2) of 0.9927. In addition, there were intentions to develop a prediction model for the dissolution rate of theophylline from the drug product. The dissolution rate of theophylline tablet was gradually delayed as the proportion of the anhydrous form was decreased. The multivariate data analysis was performed to correlate the THz spectra of theophylline tablets with the dissolution rate. The calibration model used to predict the percentage of theophylline dissolved in 45 min from the THz spectra achieved an RMSECV of 3.29%, a slope of 0.9260 and an R(2) of 0.9423. Furthermore, there were no significant differences between the predicted and measured percentages of theophylline dissolved in 45 min in the theophylline tablets that were stored at 84% relative humidity (RH) and 25 °C for 12 h or 3 d.     

Reaction of aluminium chloride with poly(divinyl benzene) particles--a reaction kinetic study using infrared spectroscopy

Porous poly(para-divinylbenzene) and poly(meta-divinylbenzene) particles were synthesised from para-divinylbenzene and meta-divinylbenzene monomers with toluene and 2-ethylhexanoic acid as porogens. The residual vinyl groups in the particles were thereafter reacted using aluminium chloride with dichlorobenzene as a catalyst. The conversion of vinyl groups was followed by analysing polymer particles taken from the reaction mixture at different time intervals. Infrared spectroscopy both in the mid and near infrared region was used as the analytical technique. The intensity changes in the overtone absorption at 1628 nm due to the vinyl bonds were used as the basis for the quantification of the vinyl group consumption. Infrared spectra of the particles in the mid IR were also measured to understand changes taking place in the polymer matrix during the reaction. The results indicated that residual vinyl groups in these polymer particles were consumed during the reaction with aluminium chloride. The reaction of aluminium chloride with the polymer matrix was explained by proposing mechanisms for the formation of different products during the reaction. The complex formed between aluminium chloride and the residual vinyl groups seemed to induce addition of HCl to the vinyl group or leads to crosslinking and/or cyclisation in the case poly(para-DVB) particles. The reaction of aluminium chloride with poly(meta-DVB) takes place to a lesser extent.     

现场FT-IR光谱电化学方法研究介稳态金属卟啉的红外光谱. Ⅰ.

本文以现场FT-IR光透薄层光谱电化学方法详细研究了介稳态锰卟啉的红外光谱。结果表明TPPMn(Ⅲ)Cl的1490cm^-^1, 1344cm^-^1, 1204cm^-^1,1010cm^-^1, 806cm^-^1处吸收峰对中心金属氧化态敏感, 随中心金属氧化态降低上述吸收峰向低波数方向移动; 而当TPPMn(Ⅲ)Cl失去一个电子形成一价阳离子自由基时, 光谱呈现较特殊的变化, 在1287cm^-^1处呈现[TPPMn(Ⅲ)Cl]^+阳离子自由基的特征吸收。     

Synthese und struktur von dicyclopentadienyl(trimethylsilyl)titanchlorid

Dicyclopentadienyl(trimethylsilyl)titanium chloride, a stable trimethylsilyltitanium compound, is synthesized by reaction of dicyclopentadienyltitanium dichloride and tris(trimethylsilyl)aluminium, coordinated with diethyl ether, or lithium tetarakis(trimethylsilyl)aluminate. The IR and NMR spectra are reported. The crystal structure of the title compound has been determined. It shows a distorted tetrahedral surrounding of the titanium atom; the Ti–Si distance is 267 pm.     

Infrared spectroscopy of goethite dehydroxylation. II. Effect of aluminium substitution on the behaviour of hydroxyl units

Dehydroxylation of goethite as affected by aluminium substitution was investigated using Fourier transform infrared spectroscopy (FT-IR) in conjunction with X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential thermogravimetric analysis (DTGA). The band intensities of hydroxyl vibrations were indicative of the degree of dehydroxylation and the changes in band parameters due to aluminium substitution were observed. The effect of aluminium substitution on band parameters of FT-IR spectra of goethite and its partially and fully dehydroxylated products, the mixture of goethite/hematite and hematite, were interpreted. The results of this study have confirmed that aluminium substituted goethite is thermally more stable than non-substituted goethite and is in harmony with the results of XRD and DTGA. A larger amount of non-stoichiometric hydroxyl units is associated with a higher aluminium substitution. A shift to a higher wavenumber of bending and hydroxyl stretching vibrations is attributed to the effects of aluminium substitution associated with non-stoichiometric hydroxyl units on the a-b plane relative to the b-c plane of goethite. The results provide information for the characterisation of activated bauxite containing hematite and goethite.     

A chemical study of thermally activated chromic titanate on silica ethylene polymerization catalysts

Thermally activated ethylene polymerization catalysts which contain chromium and titanium on silica differ from those catalysts which contain only chromium on silica. The characteristics of chromium-titanium catalysts vary with the method of incorporating the titanium and the thermal activation procedure. Titanated catalysts of the kind examined in this article have faster initiation and a higher polymerization rate per unit catalyst weight than corresponding catalysts without titanium. High-density polyethylene produced by this type of titanium-chromium catalyst tends to have a higher melt index and a broader molecular weight distribution than polyethylene made with chromium on silica catalysts. Iodometric titration showed that reduction from the initial hexavalent chromium to trivalent occurs when the dry, catalyst starting material is treated with titanium tetraisopropoxide. A study of the reaction between chromium trioxide and titanium tetraisopropoxide in carbon tetrachloride revealed that (1) it is not necessary to have a reaction between surface silanols and titanium tetraisopropoxide for the reduction to occur, and (2) the reaction product has an absorption near 660 nm in the visible range. Comparison of spectra showed that chromium trioxide on silica reduced by isopropyl alcohol has a shifted absorption, i.e., 600 nm. These findings are interpreted to mean that titanium atoms come sufficiently close to chromium atoms to change their electron density in the starting material and remain close neighbors in the activated catalysts. The interpretation is further supported by ESCA data and leads to the proposal that in this case the activated catalysts contain titanium chromate structures.     

Synthesis of some new bis-3,4-dihydropyrimidin-2(1H)-ones by using silica-supported tin chloride and titanium tetrachloride

<正>Silica-supported tin chloride and titanium tetrachloride were prepared by the reaction of tin chloride and titanium tetrachloride with activated silica gel in refluxing toluene.These solid acids have been employed as the catalysts for the synthesis of bisdihydropyrimidin -2(1H)-ones from aromatic dialdehydes,1,3-dicarbonyl compounds and urea at 90℃under solvent-free conditions.