新型除草剂威霜合成方法的改进

以对硝基氯苯为原料，经四步合成制各间体２，６－二氯苯并恶唑，以对苯二酚和２－氯丙酸为原料，经一步合成了另一中间体２－（４－羟基苯氧基）丙酸乙酯，两个中间体在二甲亚砜溶剂中，碳酸钠存在下缩合得标题化合物，全程收率为４３％。     

新型除草剂威霸合成方法的改进

以对硝基氯苯为原料，经四步合成制得中间体２，６－二氯苯并口恶唑；以对苯二酚和２－氯丙酸为原料，经一步合成了另一中间体２－（４－羟基苯氧基）丙酸乙酯，两个中间体在二甲亚砜溶剂中，碳酸钠存在下缩合得到标题化合物，全程收率为４３％。     

乙烯／顺丁烯二酸酐共聚物为主链的光致变色苯氧基萘并萘醌聚合物

通过由３－溴丙－１－醇（１）与６－［４－（２－（４－羟基苯基）异丙基）苯氧基］－５,１２－萘并萘醌（２）反应制备新反应试剂６－［４－（２－（４－（３－羟基丙氧基）苯基）异丙基）苯氧基］－５,１２－萘并萘醌（３）,然后通过（３）与乙烯－顺丁烯二酸酐交替共聚物反应的方法成功合成了乙烯－顺丁烯二酸酐为主链的光致变色苯氧基萘并萘醌聚合物（４）。与化合物（２）相似,聚合物（４）具有正常的光致变色行为。同时发现,溶剂对聚合物（４）和化合物（２）的光诱导ｔｒａｎｓ→ａｎａ异构化反应速度有明显影响。在ＴＨＦ／Ｈ２ＳＯ４（Ｖ／Ｖ＝２４／１）中的速度常数约为在ＤＭＳＯ／Ｈ２ＳＯ４（Ｖ／Ｖ＝２４／１）中的速度常数的两倍     

1,4—二苯基—2—苯氧基—1,4,2—二氮磷杂环戊—5—酮的合成及其除草活性研究

利用１，３－二苯基脲与亚磷酸三苯酯和取代苯甲醛进行的类Ｍａｎｎｉｃｈ反应合成了１，４－二苯基－２－苯氧基－１，４，２－二氮磷杂环戊－５－酮（２），所有新化合物的结构均经元素分析、ＮＭＲ、ＭＳ证实。对目标化合物进行的除草活性测试结果表明，２对阔叶杂草具有较好的选择性除草活性。     

“一锅法”简便合成1,4—双（2,4—二羟基苯基）—丁二酮—1,4

１，４－双（２，４－二羟基苯基）丁二酮－１，４－是Ｐｒａｋａｓｈ等从买麻藤属龈（ＧｅｎｅｈｕｍＵＬａ）中分离得到的一种微量组分。文中报道了以丁二腈和间苯二酚为原料，“一锅法”简便合成了此化合物。     

4,4‘二氯二苯砜部分水解制取4—氯—4’羟基二苯砜

用高效液相色谱法对４，４＇－二氯二苯砜（双氯），４，４＇－二羟基二苯砜（双酚）及４－氯－４＇－羟基二苯砜（单酚）进行了完全的分离，研究双氯部分水解制单酚发现，ＮａＯＨ用量越大，反应温度越高，水解速度越快，极值产率却越低；副产物双酚的含量随着反应时间增加，超过极值单酚产率的，由于副产物的增加，产率相对降低，最佳水解条件为水解温度１３５－１４０℃，ＮａＯＨ／双氯（摩尔比）为３．２５：１水解时间２．５－     

扁桃酸及其类似物在全甲基环糊精固定相上的手性拆分

在全甲基β－环糊精（ＰＭＢＣＤ）和全甲基γ－环糊精（ＰＭＧＣＤ）手性固定相上,考察了扁桃酸酯、α－甲氧基扁桃酸酯、２－羟基－３－苯基丙酸酯和２－羟基－４－苯基丁酸乙酯的气相色谱手性分离行为。结果表明,所有研究的羟基羟基羧酸酯均可以在ＰＭＣＤ手性固定相上得到很好的手性分离,而ＰＭＧＣＤ对所研究的对映体没有任何手性拆分能力。结合和学参数,探讨了手性诉分机理。     

1—对甲苯磺酰基—2—氧代—2—苯氧基—3—芳基—1,4,2—二氮…

通过１－苯基本磺酰基硫脲（１）与亚磷酸三苯酯和取代苯甲醛在甲苯中进行的类Ｍａｎｎｉｃｈ反应合成１－对甲苯磺酰基－２－氧代－２－苯氧基－３－芳基－１，４，２－二氮磷杂环戊－５－硫酮（２）。本文对合成过程中所涉及到的副反应进行了初步探讨。     

稀土（Nd,Pr）（Ⅲ）双酞菁衍生物的合成,表征和气敏特性

合成了八－４－（四氢糖氧基）酞菁钕（Ⅲ）（Ａ）、八－４－（β－萘氧基）酞菁钕（Ⅲ）（Ｂ）、八－４－（２，４－二叔戊基苯氧基）酞菁钕（Ⅲ）（Ｃ）和八－４－（２，４－二叔戊基苯氧基）酞菁镨（Ⅲ）（Ｄ）４种新的稀土（Ｎｄ、Ｐｒ）（Ⅲ）双酞菁衍生物，经元素分析、红外光谱、核磁共振谱表征。紫外可见光谱表明，它们在氯仿（１０＾－６ｍｏｌ／Ｌ）溶液中以单分子形式存在。热重分析证明配合物的热稳定性：Ｂ＞Ｃ￣Ｄ＞Ａ     

2—氯／2—甲磺酰基—5—（2—苯基—4—喹啉基）—1,3,4—恶二唑…

借处理２－羟基－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑同ＰＣｌ５／ＰＯＣｌ３之间的反应合成了２－氯－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑（３）和通过２－Ｙｕ基－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑的甲基化，然后氧化制得２－甲磺酰基－５－（２－苯基－４－喹啉基）－１，３，４－恶二唑（６）。并分别研究了３和６同胺、叠氮及肼的反应，得到２，５－二取代的恶二唑新衍生物。初     

Separation of Enantiomers of 2-(4-hydroxyphenoxy) Propionic Acid and its Esters by HPLC

(±)-2-(4-hydroxyphenoxy) propionic acid and its esters are the important intermediates of the preparation of herbicides such as fenoxaprop, quizalofop-P, fluazifop-P-butyl,fenthiaprop, haloxyfop and so on, especially, (+)-2-(4-hydroxyphenoxy) propionic acid and its esters using as intermediates of the preparation of super-high efficient herbicides.Presently, the separation of the enantiomer of 2-substituted phenoxy propionic acid and its esters had been reported.     

Preparation of single-enantiomer 2-methyl-4-heptanol, a pheromone of Metamasius hemipterus, using (S)-2-methoxy-2-(1-naphthyl)propionic acid

To investigate the resolution of secondary alcohols using 2-methoxy-2-(1-naphthyl)propionic acid (MalphaNP acid), 2-methyl-4-heptanol, one of the aggregation pheromones of Metamasius hemipterus, was resolved using (S)-MalphaNP acid. As a chiral-resolving agent, MalphaNP acid is superior to 3,3,3-trifluoro-2-methoxy-2-phenylpropionic acid (MTPA) in terms of HPLC separation and NMR shielding. A better separation of diastereomeric MalphaNP esters was observed when n-hexane-THF was used as the eluent for silica gel HPLC. The solvolysis of the diastereomeric MalphaNP esters gave (R)-2-methyl-4-heptanol and its enantiomer; enantiopure (S)-MalphaNP acid was also recovered. In addition, the preferred conformation of the MalphaNP ester was confirmed using methyl (R)-3-hydroxyvalerate as an authentic compound.     

Enantiomeric separation of chiral phenoxy acid herbicides by electrokinetic chromatography. Application to the determination of analyte-selector apparent binding constants for enantiomers

The enantiomeric resolution of chiral phenoxy acid herbicides was performed by electrokinetic chromatography using a cyclodextrin as chiral pseudophase (CD-EKC). A systematic evaluation of several neutral and charged cyclodextrins was made. Among the cyclodextrins tested, (2-hydroxy)propyl beta-cyclodextrin (HP-beta-CD) was found to be the most appropriate for the enantioseparation of phenoxy acids. The influence of some experimental conditions, such as nature and pH of the background electrolyte, chiral selector concentration, and temperature, on the enantiomeric separation of phenoxy acids was also studied. The use of a 50 mM electrolyte solution in ammonium formate at pH 5 and a temperature of 40 degrees C enabled the enantiomeric resolution of four of the six phenoxy acids investigated (2-phenoxypropionic acid, 2(3-chlorophenoxy)propionic acid, 2-(4-chlorophenoxy)propionic acid, and 2-(2,4-dichlorophenoxy)propionic acid) obtaining migration times ranging from 9 to 15 min. Mixtures of the two phenoxy acids not enantiomerically resolved (2-(4-chlorophenoxy)-2-methylpropionic acid and 2-(2,4,5-trichlorophenoxy)propionic acid) and up to three of the phenoxy acids enantiomerically resolved were separated in about 15 min. Finally, the apparent binding constants for each enantiomer-HP-beta-CD pair were calculated at two temperature values (20 and 40 degrees C).     

反相液相色谱法分离2-(4-羟基苯氧基)丙酸酯对映体

合成了三-(4-甲基苯甲酸)纤维素酯(MCTB)手性固定相，用反相高效液相色谱法在该手性固定相上对2-(4-羟基苯氧基)丙酸酯对映体进行拆分．实验结果表明，在三-(4-甲基苯甲酸)纤维素酯手性固定相上，以甲醇与水的体积分数为75：25做流动相能较好的拆分2-(4-羟基苯氧基)丙酸甲酯、乙酯和丁酯对映体，其分离因子分别为1．38、1．49、0．98；同时还发现2-(4-羟基苯氧基)丙酸酯中酯基团的大小对其对映体的分离也有明显的影响，其中以乙酯的拆分效果最佳。     

2，6-二-O-乙氧乙基-3-O-三氟乙酰基-β-环糊精气相色谱手性固定相的制备及应用

将β-环糊精的2,6-位引入乙氧乙基,3-位引入三氟乙酰基,合成了新的环糊精衍生物2,6-二-O-乙氧乙基-3-O-三氟乙酰基-β-环糊精,并采用静态法涂渍毛细管气相色谱柱,考察了毛细管柱的柱性能和分离性能。结果表明,该固定相对G rob试剂、苯的二取代位置异构体氯甲苯、硝基甲苯和溴甲苯以及10种手性化合物如α-取代丙酸酯化合物、1-(2′-硝基苯基)-乙醇、α-甲基-对氯苯乙腈和丙炔醇酮乙酸酯等具有良好的分离效果。其中,对α-甲磺酰基丙酸酯对映体的拆分效果最好;对α-取代丙酸的甲酯衍生物的分离效果优于乙酯衍生物;对α-羟基取代丙酸酯的分离效果优于α-卤代丙酸酯。     

3-(2-氧代环烷基)丙酸与(R)-2-硫代四氢噻唑-4-羧酸乙酯的反应

３－（２－氧代环烷基）丙酸与（Ｒ）－２－硫代四氢噻唑－４－羧酸乙酯的反应李叶芝,田颜清,黄化民（吉林大学化学,长春,１３００２３）关键词（Ｒ）－２－硫代四氢噻唑－４－羧酸乙酯,Ｎ－３－（２－氧代环烷基）丙酰－２－硫代四氢噻唑－４－羧酸乙酯,环合反应,...     

高效液相色谱法分离2-(4-羟基苯氧基)丙酸酯的对映体

采用高效液相色谱法在手性柱上分离芳氧基苯氧基丙酸类除草剂中间体(±)-2-(4-羟基苯氧基)丙酸酯的对映体。实验结果表明,在三苯甲酸纤维素酯的手性柱上,以无水乙醇为流动相能较好地分离(±)-2-(4-羟基苯氧基)丙酸乙酯和甲酯,其分离因子α值分别为1.44和1.29;同时还发现在三苯甲酸纤维素酯的手性柱上2-取代芳氧基或芳基丙酸酯结构中的酯基团的大小对其对映体的分离有明显的影响,其中以乙基为最佳。并通过对照试验证实了2-(4-羟基苯氧基)丙酸乙酯的右旋体先流出,其左旋体后流出。     

Utilization of zirconia stationary phase as a tool in drug control

Zirconia-based stationary phases represent an interesting alternative to silica-based materials. Two zirconia-based stationary phases were studied as an option for use in drug analysis. The different properties of zirconia material, distinct from RP silica-columns, were employed for the development of a novel and rapid stability monitoring HPLC method. This method enables simultaneous control of possible degradation processes of active substance (ibuprofen) as well as antimicrobial excipients (methyl-and propylparaben). The separation of ibuprofen, its two main degradation products 2-(4-isobutyrylphenyl)propionic acid and 4-isobutylacetophenone, parabens, and 4-hydroxybenzoic acid as their degradation product was successfully accomplished on a Zr-CarbonC18 column using a mobile phase consisting of acetonitrile-phosphate buffer (pH 4.8)-propan-2-ol (27:56:17, v/v/v). Detection was performed at 258 nm and the analysis was completed within 17 minutes.     

Development and validation of a capillary electrophoresis method for the measurement of short-chain organic acids in natural rubber latex

Short-chain organic acid contents in serum of natural latex are interesting to measure and capillary electrophoresis (CE) has proved to be a good tool for their study. In the present work a method has been developed to identify the short-chain organic acids present in sera of natural rubber latex (oxalic, formic, fumaric, aconitic, succinic, malic, glutaric, citric, acetic, glycollic, propionic and quinic acids), the separation was optimised and the quantification method validated. The separation was performed on a CE system with UV detection at 200 nm. The separation was carried out with an uncoated fused-silica capillary (57 cm x 50 microm I.D.) and was operated at -10 kV potential. The separation buffers were prepared with 0.5 M H3PO4, 0.5 mM cetyltrimethylammonium bromide and pH adjusted by adding NaOH to 6.25 except for propionic acid which was better measured at pH 7.00. Validation parameters are adequate and limits of detection range from 0.005 mM to 1.6 mM. Short-chain organic acids were measured with this method in sera of three different types of latex.     

整体柱在线固相微萃取-高效液相色谱同步富集检测水中的苯氧羧酸类除草剂

采用C18毛细管整体柱作为固相微萃取整体柱,构建在线固相微萃取-高效液相色谱联用系统,同步富集检测环境水样中的5种苯氧羧酸类除草剂。详细考察了联用系统运行条件对富集检测的影响。联用系统运行最佳参数为:固相微萃取整体柱长度20 cm,进样流速0.04 mL/min,进样13 min,洗脱流速0.02 mL/min,洗脱5 min。在最佳条件下,5种苯氧羧酸类除草剂的检出限为:9 μg/L (苯氧丙酸)、4 μg/L (2-(2-氯)-苯氧丙酸)、4 μg/L (2-(3-氯)-苯氧丙酸)、5 μg/L (2,4-二氯苯氧乙酸)、5 μg/L (2-(2,4-二氯苯氧基)丙酸)。与HPLC系统直接进样对比,联用系统对5种检测对象表现出优良的富集能力。5种苯氧羧酸类除草剂的回收率在79.0%~98.0%之间(RSD≤3.9%)。该方法成功应用于水样中5种苯氧羧酸类除草剂的检测,结果令人满意。