联苯氯甲基化反应的研究

以联苯、多聚甲醛为起始原料,氯化锌/H2O为催化剂,在氯化氢的存在下经氯甲基化反应,得到了4,4’-二氯甲基联苯。讨论了反应温度和时间对反应产率及产品纯度的影响。并利用气相色谱质谱联用仪对产物中的杂质进行了定性分析。     

苯巴比妥原料药中的两个杂质及其含量测定

在苯巴比妥原料药中分离得到两个杂质,实验经过MS和IR对其定性,确定杂质分别是α-苯丁酰胺和甲基苯巴比妥;实验采用气相色谱法对苯巴比妥原料药中两个杂质的含量进行测定,以氮气为载气,DB-1701毛细管柱为固定相,α-苯丁酰胺和甲基苯巴比妥达到基线分离,精密度(RSD%)分别为2.1%和1.9%,回收率分别为102%和98%,结果准确可靠,可以用气相色谱法控制含量。     

工业联苯气相色谱分析

采用气相色谱法有效地对工业联苯进行了测定。以色—质联用作了定性分析,用内标法和差减法作了定量分析比较,结果一致。工业联苯的质量分析,国内一直采用物理方法,如测熔点;残炭;苯溶解试验等。这些方法不能准确反映联苯纯度及杂质成     

4-甲基联苯的合成研究

以对甲基苯胺为原料,经重氮化,与哌啶合成4-甲基苯三氮烯,然后在有机酸催化下与苯反应两步合成了4-甲基联苯.4-甲基苯三氮烯的合成收率为89.8%,4-甲基联苯的二步合成总收率为51.2%.     

氯氰菊酯农药中杂质及立体异构体的分离、鉴定

本文应用薄层色谱、气相色谱法分离了氯氰菊酯原药中的立体异构体和主要杂质。经GC-MS鉴定,其主要杂质为3-(2,2-二氯乙烯基)2,2-二甲基环丙烷羧酸,3-含氧基苯基安息香醛,3-含氧基苯基安息香醇及3-含氧基甲基偶联苯。它们与该农药在动物和土壤中的主要代谢物相同。     

气相色谱法测定邻氨基苯乙醚及其有机杂质

采用气相色谱对邻氨基苯乙醚及其有机杂质进行分离,用峰面积归一化法进行定量分析。通过气相色谱-质谱联用仪对邻氨基苯乙醚及其有机杂质进行分离并定性。使用精密度数据对分析方法进行了评价,给出了各杂质的最小定量限。     

气相色谱法测定对氨基苯乙醚及其有机杂质

采用气相色谱对对氨基苯乙醚及其有机杂质进行分离,用峰面积归一化法进行定量分析。通过气相色谱-质谱联用仪对对氨基苯乙醚及其有机杂质进行分离并定性,给出了各化合物的结构式及结构信息。使用精密度数据对分析方法进行了评价。     

3,5-二甲基苯胺的气相色谱分析

采用PEG-20M和Chromosorb WAW DMCS栽体组成的固定相,在填充拄上分离了3,5-二甲基苯 胺及其异构体杂质.以联苯为内标,对3,5-二甲基苯胺样品进行了定量分析.方法的相对标准偏差为 0.39％,相对误差为-0.091％～0.13％,该方法已用于3,5-二甲基苯胺的研制中。     

4,4’-双(三氟甲基)-2,2’-二氨基联苯的合成

以4-溴-2-硝基三氟甲基苯、铜粉为原料经Ullmann反应,得到4,4’-双(三氟甲基)-2.2’-二硝基联苯,钯碳催化还原合成得到4,4’-双(三氟甲基)-2.2’-二氨基联苯,再以5%Pd/C为催化剂,H2为还原剂,在乙醇中将4,4’-双(三氟甲基)-2.2’-二硝基联苯还原得到4,4’-双(三氟甲基)-2.2’-二氨基联苯。4,4’-双(三氟甲基)-2.2’-二氨基联苯的总收率为81.3%,纯度为99.5%,APHA值小于100。     

德国禁用芳香族氨基化合物及其偶氮染料

1994年7月,德国颁布法令,自1995年起,禁止用联苯胺、4-氨基联苯、4-氯-2-甲基苯胺、2-萘胺、4-氨基-3、2′-二甲基偶氮苯、2-氨基-4-硝基甲苯、对氯苯胺、2,4-二氨基苯甲醚、4,4′-二_氨基二苯甲烷、3,3′-双氯联苯胺、3,3′-二甲氧基联苯胺、3,3′-二甲基联苯胺、3,3′-二甲基-4,4′-二氨基二苯甲烷、3-甲基-6-甲氧基苯胺、4,4′-二氨基-3,3′-二氯二苯甲烷、4,4′-二氨基二苯醚、4,4′-     

气相色谱单柱快速分析吡虫啉中间体

本文提出了在同一条件下２，（Ｎ，Ｎ－二甲基）氨基－５－甲基吡啶和２－氨基－５－甲基吡啶气相色谱分析方法。本方法以１０％ＯＶ－１０１／Ｃｈｒｏｍｏｓｏｒｂ Ｗ ＡＷ ＤＭＣＳ为固定相，采用程序升温法实现对３－甲基吡啶，Ⅰ，Ⅱ及其杂质的有效分离。     

洗油精细加工现状与绿色分离过程开发

煤焦油洗油中分离产物在农药、医药、染料、加工助剂及工程塑料等领域有着广泛的应用。目前分离洗油中α-甲基萘、β-甲基萘、喹啉、联苯、吲哚、苊及芴等普遍采用精馏重结晶方法,该方法耗能大、污染大,因此研究探讨洗油加工中的绿色分离过程是十分有必要的。绿色分离过程的主要绿色分离方法有反应精馏、绿色溶剂流体萃取及膜过程。开发绿色分离工艺对于洗油深加工方面具有一定的科研价值和工业前景。     

Synthesis and thermal stability,dielectric, and conductivity characteristics of some carbazole-bearing pendant and backbone sulfones

A group of poly(N-vinylcarbazole) pendant polysulfones has been prepared by reacting it with benzene, toluene, p-chlorobenzene- and p-nitrobenzenesulfonyl chloride and N-methyl carbazole, 3,6-disulfonyl chloride by the Friedel Crafts reaction. Carbazole-based backbone polysulfones have also been prepared by the reaction of N-methyl carbazole, 3,6-disulfonyl chloride and biphenyl, naphthalene, anthracene, and carbazole in presence of anhydrous aluminum chloride. The various sulfone polymers, thus prepared, have been structurally characterized by elemental analysis and IR spectroscopy. Detailed analyses of thermal stability, dielectric, and conductivity characteristics have revealed certain significant differences between these two types of sulfone polymers.     

LC-MS/MS鉴定阿齐沙坦降解产物

以1%甲酸溶液-乙腈为流动相,经C18柱（250 mm×4.6 mm,5μm）分离,通过串联ESI质谱在线检测,获得相关的色谱和质谱信息。根据研究结果推测光降解主要产物为1-（（2＇-1H-双吖丙啶-3-基-[1,1＇-联苯]-4-基）甲基）-2-乙氧基-1H-苯并[d]咪唑-7-羧酸,酸降解主要产物为2-氧代-3-（（2＇-（5-氧代-4,5-二氢-1,2,4-噁二唑酮-3-基）-[1,1＇-联苯]-4-基）甲基）-2,3-二氢-1H-苯并[d]咪唑-4-羧酸。     

Challenges in Catalytic Manufacture of Renewable Pyrrolidinones from Fermentation Derived Succinate

Fermentation derived succinic acid ammonium salt is an ideal precursor for manufacture of renewable N-methyl pyrrolidinone (NMP) or 2-pyrrolidinone (2P) via heterogeneous catalysis. However, there are many challenges to making this a practical reality. Chief among the challenges is avoiding catalyst poisoning by fermentation by- and co-products. Battelle/Pacific Northwest National Laboratory have developed an effective technology strategy for this purpose. The technology is a combination of purely thermal processing, followed by simple catalytic hydrogenation that together avoids catalyst poisoning from fermentation impurities and provides high selectivity and yields of NMP or 2P.     

Application of GPC in the Study of Stereospecific Block Copolymers

Abstract

Three different techniques involved in the preparation of Stereospecific block copolymers were studied using gel permeation chromatography (GPC). These techniques involved the use of a monofunctional organo-lithium catalyst, a difunctional organolithium catalyst, and a combination of a monofunctional organolithium catalyst and a coupling technique. GPC curves were obtained on the block copolymers using two different column sequences and solvents. The ABA block copolymers studied contained styrene, vinyl toluene, or α-methyl styrene as thermoplastic monomers and butadiene as the elastomeric monomer. The results obtained showed that block copolymers prepared using monomers and catalyst systems free of impurities generally exhibited single peaked GPC curves. In systems where impurities were found to be present, small amounts of A block homopolymer and AB block copolymer were formed. In such cases, the GPC curves were observed to have two or three peaks.     

Synthesis and mesomorphic behavior of terminally carboxyl oligo(ethylene oxide) monomethyl ethers-substituted side chain liquid crystalline polysiloxanes. I

A series of alkene monomers containing carboxyl biphenyl benzoate ester or carboxyl p,p′-phenyl benzoate ester based on mesogenic core with a carboxyl (±)-2-methyl ethylene glycol monomethyl ether group or various lengths of carboxyl oligo (ethylene oxide) monomethyl ethers as the terminal group were synthesized. And they were grafted onto the poly(methylhydrosiloxanes) (PMHS) by the platinum catalyzed hydrosilylation process. Their molecular structure, the thermal transitions temperature, and mesophase texture of monomers and of polymers were characterized using ¹H nuclear magnetic resonance, differential scanning calorimetry, and polarizing optical microscopy with hot stage. The polymers obtained all show smectic phase while their precursor monomers show both smectic and/or nematic phase, or in some cases, no mesophase. The factors governing mesophase texture and transition temperature are discussed. © 1993 John Wiley & Sons, Inc.     

Challenges in Catalytic Manufacture of Renewable Pyrrolidinones from Fermentation Derived Succinate

Fermentation derived succinic acid ammonium salt is an ideal precursor for manufacture of renewable N-methyl pyrrolidinone (NMP) or 2-pyrrolidinone (2P) via heterogeneous catalysis. However, there are many challenges to making this a practical reality. Chief among the challenges is avoiding catalyst poisoning by fermentation by- and co-products. Battelle/Pacific Northwest National Laboratory have developed an effective technology strategy for this purpose. The technology is a combination of purely thermal processing, followed by simple catalytic hydrogenation that together avoids catalyst poisoning from fermentation impurities and provides high selectivity and yields of NMP or 2P.

     

Poly(ethyene terephthalate)–solvent interaction: Gelation and melting point depression

The interactions between poly(ethylene terephthalate) (PET) and six high temperature solvents are discussed in terms of gelation and melting temperature depression. The six solvents are 1′-acetonaphthone (AN), phenyl ether (PE), biphenyl (BP), 1-methyl naphthalene (MN), nitrobenzene (NB), and a eutectic mixture of phenyl ether and biphenyl (EU). Although the six solvents have very similar solubility parameter values, the dissolution, gelation, and gel melting temperatures of the PET-solvent systems are vastly different. The characteristic transition temperatures (dissolution, gelation, and gel melting temperatures) of the six solvents decrease in the following order: PE > EU > BP > MN > AN > NB, which is the reverse order of the solvent power. While the transition temperatures of the gel vary with the solvent system, the melting temperature of the dry gel formed from quiescent solution is independent of solvent system. That is, PET-solvent interactions are only discernible in solvated state (wet gel). All the experimental results suggest crystallization is the primary cause of gelation of high temperature PET solutions, with crystals acting as junction points in the network. Based on the dissolution and gel melting temperatures, interaction parameters for the six PET-solvent systems have been calculated.     

Effect of purification of 2-methyltetrahydrofuran/ethylene carbonate mixed solvent electrolytes on cyclability of lithium metal anodes for rechargeable cells

The effects of the purification of LiAsF₆–2-methyl tetrahydrofuran (2MeTHF)/ethylene carbonate (EC) mixed solvent organic electrolytes on the charge–discharge cyclability of lithium metal anodes has been investigated by using an accelerated method for evaluating lithium cycling efficiency. This method involves cycle tests on coin cells with an amorphous V₂O₅–P₂O₅ (95:5 molar ratio) cathode and an anode containing a small amount of lithium. Using this method, the cycle life of the cell was determined over a short period simply from the lithium cycling efficiency. The lithium cycling efficiency in LiAsF₆–2MeTHF/EC was improved by removing both water and organic impurities such as peroxides. An electrolyte containing less than 14ppm of water and 20ppm of organic impurities had a high lithium cycling efficiency of 97.2%.