二氯丙醇环化制备环氧氨丙烷的工艺及动力学研究

考察了各种因素对二氯丙醇环化反应的影响,以及无机盐NaCI的存在对粗环氧氯丙烷（ECH）溶液浓度的影响。建立了环化反应的动力学模型并验证了其正确性,得到了二氯丙醇环化反应的动力学参数。结果表明,二氯丙醇环化的最佳反应条件为：二氯丙醇与NaOH的摩尔比为1：1．2,环化温度为75℃、反应时间为90s。二氯丙醇环化反应为二级反应,1,2-二氯丙醇和1,3-二氯丙醇环化反应的活化能分别是94．19kJ／mol和92．23kJ／mol。     

四氯化碳与镁的反应及其反应机理的研究──产生二氯卡宾的新方法

四氯化碳与镁的反应及其反应机理的研究──产生二氯卡宾的新方法林海霞,徐良衡,黄乃聚（温州师范学院化学系,温州,３２５００３）（复旦大学化学系）关键词二氯卡宾,偕二氯环丙烷衍生物,单电子转移偕二氯环丙烷衍生物是一类重要的有机合成中间体,它主要通过二氯卡...     

甲醛还原法制备2,2'-二氯氢化偶氮苯

二氯氧化偶氮苯;二氯联苯胺;还原过程;甲醛还原法制备2;2'-二氯氢化偶氮苯     

2-氯吡啶气相光氯化反应机理的量子化学研究

用量子化学DFT方法在B3LYP/3-21G^*水平下研究了2-氯吡啶气相光氯化取代反应生成2,3-二氯吡啶、2,4-二氯吡啶、2,5-二氯吡啶和2,6-二氯吡啶不同产物的过渡态,并计算了活化能.结果表明,生成2,6-二氯吡啶过渡态的能量最低,所需的活化能也最低,反应优先生成2,6-二氯吡啶.生成2,6-二氯吡啶的IRC结果显示反应过程中C-H键的断裂和C-C l键的生成协同但不同步.过渡态的构型接近于产物,是一个晚期过渡态.C l原子在反应进程中是给电子的,因此,氯自由基与2-氯吡啶反应是亲核取代的SN2机理.     

3,6-二氯-2-氨基吡啶合成新方法

本文报道了3,6-二氯-2-氨基吡啶的两种新合成方法。第一种方法:以3,6-二氯-2-吡啶甲酸为原料,经过酰氯、酰胺中间体,再霍夫曼降解得到3,6-二氯-2-氨基吡啶;第二种方法:以戊二酰亚胺为原料,采用三氯氧磷进行氯化反应,合成中间体2,3,6-三氯吡啶,经过氨化反应得到3,6-二氯-2-氨基吡啶。并对两种合成方法进行了简单对比。最后以合成的3,6-二氯-2-氨基吡啶为原料进一步合成了3,6-二氯-2-氟吡啶。     

二茂钛二甘氨酸盐酸盐与DNA作用机理的研究

二氯二茂钛是一种活性很高的抗肿瘤药物,对它的抗肿瘤机理目前尚无定论．我们用核磁共振方法研究二氯二茂钛与单核苷酸的成键特点时发现[1],二氯二茂钛与核苷酸的成键方式既不同于顺铂,又不同于二氯二茂钼、二氯二茂钒等,表明其抗肿瘤机理可能与顺铂有明显不同．由于二氯二茂钛在水中的溶解度不大,故妨碍了对它与DNA作用机理的进一步研究．最近,二氯二茂钛与甘氨酸形成的配合物──二茂钛二甘氨酸盐酸盐,已被成功地合成出来[2]．由于它极易溶于水,且其酸性配体为氨基酸,因此研究该化合物的抗肿瘤活性及其与DNA的作用特点,对了…     

一种1,1-二氯烯烃化合物的新合成方法

1,1-二氯烯烃结构存在于许多天然产物中,同时也是一类重要的合成中间体,广泛应用于炔烃、卤代炔烃以及芳烃化合物的合成.报道了一个新的1,1-二氯烯烃化试剂:二氯甲基(2-吡啶基)砜.以叔丁醇钾作为碱,二氯甲基(2-吡啶基)砜与芳香醛顺利反应,以良好的产率制备得到了1,1-二氯烯烃化合物.该方法实验操作简便、试剂易得且纯化方便.     

液下单液滴微萃取-高效液相色谱法测定二氯酚

采用液下单液滴微萃取样品处理方法富集水中的2,4-二氯酚和2,6-二氯酚,高效液相色谱法测定.考察了不同萃取剂、萃取条件及测定条件对检测结果的影响.2,4-二氯酚和2,6-二氯酚的线性范围分别在0.001～20 mg/L和0.003～20 mg/L之间,检出限分别为0.001和0.003 mg/L.     

N-二氯乙酰基噁唑烷合成反应的薄层色谱法研究

用薄层色谱法监测了用二氯乙酰氯、醇胺和酮合成的除草剂的安全剂N 二氯乙酰基 口恶唑烷的反应过程。方法操作简便、快速、准确。     

N-二氯乙酰基噁唑烷合成反应的薄层色谱法研究

 用薄层色谱法监测了用二氯乙酰氯、醇胺和酮合成的除草剂的安全剂N 二氯乙酰基 口恶唑烷的反应过程。方法操作简便、快速、准确。     

毛细管胶束电动色谱法测定夏枯草中两种有效成分

建立了毛细管胶束电动色谱法（ＭＥＫＣ）同时分离和测定夏枯草中齐墩果酸和熊果酸异构体含量的新方法。以１５ｍｍｏｌ／Ｌ磷酸氢二钠（Ｎａ２ＨＰＯ４）、１５ｍｍｏｌ／Ｌ硼砂（Ｎａ２Ｂ４Ｏ７）、１０ｍｍｏｌ／Ｌ十二烷基硫酸钠（ＳＤＳ）、５％（Ｖ／Ｖ）乙醇的缓冲溶液作为运行电解质溶液,在２０ｍｉｎ实现了齐墩果酸和熊果酸的基线分离。同时也研究了ＳＤＳ浓度和有机溶剂（乙醇）浓度对待测物质分离的影响。研究了不同提取     

氯氮平、去甲氯氮平及奥氮平的高效液相色谱电化学检测特性的研究

 采用高效液相色谱安培电化学检测法 ,考察了氯氮平、去甲氯氮平和奥氮平在不同 pH值流动相下的色谱分离情况及其色谱峰高与检测电压的关系。结果表明 ,氯氮平、去甲氯氮平和奥氮平的保留时间均随流动相 pH值的升高而延长 ;在pH值为 4 5 6和 5 5 6的流动相中 ,均可实现基线分离。 3种化合物的色谱峰高与检测电压之间呈典型的“S”型曲线 ,pH值升高时该曲线均左移。氯氮平、去甲氯氮平和奥氮平的检测电压必须大于产生最大氧化电流的最低电压才能得到稳定的检测电流。这种典型的“S”型伏安曲线对于化合物的定量和定性检测具有重要意义。     

火锅底料中罂粟壳的高效液相色谱法测定

采用高效液相色谱法,以C18柱为分析柱,V（甲醇）：V（25mmol／LKH2PO4）＝90：10为流动相,检测波长254mm,分析了火锅底料中的罂粟壳。同时以空白火锅底料及空白底料添加罂粟壳做阴性及阳性对照。实验证实该方法灵敏、准确、可靠。     

薄层色谱法在蔗糖-6-苯甲酸酯合成过程中的应用

用薄层层析法对蔗糖－６－苯甲酸酯合成过程中所涉及的反应物进行分离分析，选择 经出最佳展开剂体系为：四氢呋喃：水：乙酸＝４：６：５：０．５（ｖ／ｖ）。在该展开剂条件下，可以有效地分离反应原料、反应中间体和反应产物，较直观地指标了反应里程。     

毛细管区带电泳法快速分离硝基酚和除草剂

 运用毛细管区带电泳法 ,通过在缓冲溶液中添加多阳离子化合物改变电渗流方向的方法 ,快速分离了 11种一取代、二取代和三取代硝基酚及 4种在德国常用的除草剂Bromoxynil,DNOC ,Dinoterb和Ioxynil。使用UV检测 ,这些化合物的检测限在 0 5mg/L～ 1 1mg/L。为满足环境样品分析的要求 ,使用固相萃取方法对样品进行了预处理 ,使硝基酚的检测限达到 1μg/L以下 ,并对实际样品进行了分析。     

Redox-active ferrocene-modified pyrimidines and adenine as antitumor agents: structure,separation of enantiomers,and inhihibition of the DNA synthesis in tumor cells

The structures, electrochemical properties, enantiomeric separation of ferrocenyl-(alkyl)pyrimidines and ferrocenyl(ethyl)adenine and their effects on the DNA synthesis in tumor cells were studied. Enantiomeric mixtures were separated by HPLC on modified cellulose as the chiral selector. The electrochemical properties of compounds were studied by cyclic voltammetry. All compounds have reversible single-electron redox transition in the region of 0.52–0.60 V, which belongs to ferrocene—ferrocenium with a positive shift compared to ferrocene (0.52 V). The molecular structure of 1-N-(ferrocenylbenzyl)-5-iodocytosine was studied by X-ray diffraction. 1-N-(Ferrocenylethyl)adenine was studied for ability to inhibit the DNA synthesis in the human ovarian cancer cell culture by the ³H-thymidine test.     

Determination of volatile and non-volatile nickel and vanadium compounds in crude oil using electrothermal atomic absorption spectrometry after oil fractionation into saturates, aromatics, resins and asphaltenes

In recent work, it has been shown that electrothermal atomic absorption spectrometry (ET AAS) can be used to differentiate between volatile and non-volatile nickel and vanadium compounds in crude oil. In the present work, the distribution of these two groups of compounds over different fractions of crude oil was investigated. For this purpose two crude oil samples were separated in two steps: firstly, the asphaltenes were precipitated with n-heptane, and secondly, the maltenes were loaded on a silica column and eluted with solvents of increasing polarity. The four fractions of maltenes eluted from silica column were: F1, saturated and light aromatics; F2, polyaromatics; F3, resins; and F4, polar compounds. Fractions F1 and F2 were further investigated using gas chromatography, and all fractions were characterized by CHN analysis, confirming the increase of aromatics in the fractions 2, 3, 4 and asphaltenes. For the determination of Ni and V by ET AAS, oil-in-water emulsions were prepared. The speciation analysis was carried out measuring without chemical modifier (stable compounds) and with 20 μg palladium (total Ni and V) and the volatile fraction was calculated by difference. The limits of detection were 0.02 μg g⁻¹ and 0.06 μg g⁻¹, for Ni and V, respectively, based on an emulsion of 2 g of oil in 10 mL. The volatile species of Ni and V were associated with fractions F3 and F4, while only thermally stable Ni and V was precipitated in part together with the asphaltenes.     

Microchip capillary electrophoresis with a boron-doped diamond electrode for rapid separation and detection of purines

Microchip capillary electrophoresis (CE) coupled with a boron-doped diamond (BDD) electrode has been employed for the separation and detection of several purines and purine-containing compounds. The BDD end-channel amperometric detector offers favorable signal-to-noise (S/N) characteristics at the high detection potential (+ 1.3 V) essential for detecting purine-related compounds. Factors influencing the separation and detection processes were examined and optimized. Five purines (guanine, hypoxanthine, guanosine, xanthine, and uric acid) have been separated within 6 min at a separation voltage of 1000V using a borate/phosphate run buffer (pH 8.2). Linear calibration plots are observed for micromolar concentrations of the purine compounds. Good stability and reproducibility (R.S.D. < 5%) are obtained reflecting the minimal adsorption of purines at the BDD surface. Applicability for the detection of nucleosides, nucleotides, and oligonucleotides is illustrated. The new microchip protocol offers great promise for a wide range of bioanalytical applications involving assays of purines and purine-containing compounds.     

单壁碳纳米管+SE-30毛细管柱的制备研究及对多种物质的拆分

使用单壁碳纳米管(SWNTs)作气相色谱的固定相, 并用静态涂渍法在单壁碳纳米管内壁涂渍浓度不同的SE-30固定液. 为考察固定液浓度不同的几根毛细管柱的柱性能, 对多种物质进行了拆分, 并将该拆分结构与直接涂渍SE-30柱的毛细管柱性能进行对照. 实验结果表明: 键合了SWNTS再涂渍SE-30的毛细管柱较之直接涂渍SE-30的毛细管柱拆分效果有所改进, 但存在一定的拖尾现象. 此外, 前者对气体有较好的拆分效果, 且其效果随SE-30浓度按一定规律变化. 从分离性能来看, 键合了SWNTS再涂渍SE-30的固定相对气体的分离具有较好的效果.     

Thin-layer chromatographic detection of zeranol and estradiol in fortified plasma and tissue extracts with Fast Corinth V.

In an attempt to improve sensitivity of thin-layer chromatographic (TLC) analysis and selectivity of visualizing agents for detection of estrogenic anabolic hormones, several dyes were screened for their chromogenic interactions with estrone, estradiol, diethylstilbestrol (DES), zeranol (zearalanol), zearalanone, and mycotoxins, zearalenone and zearalenol. Fast Corinth V salt was selected for its relatively high sensitivity. These anabolic compounds were separated by TLC and visualized with Corinth V and the results compared to iodine and starch visualization. Fortified bovine plasma and tissues (kidney, liver and muscle) and chicken muscles were analyzed after a clean-up procedure using solid-phase dual columns of alumina and anion-exchange resin. Iodine-starch clearly detected 4 ng of estradiol and DES while zeranol and zearalenone were detected at higher levels (10 ng). Fast Corinth V showed distinct spots with 2 ng of zeranol and 4 ng of zearalenone while faint spots were observed with estradiol and estrone standards. DES was not detectable at these levels. Less background interference was observed with Corinth V than with iodine-starch. The former confirmed spots detected by iodine-starch. This study suggests its selectivity for detection of zeranol and its metabolite, zearalanone, in the presence of steroidal compounds.