N,N'-二(芳磺酰) 亚磺酰胺-S-(2-苯并咪唑基) 类化合物的合成

本文报道了新化合物N,N'-二(芳磺酰)亚磺酰胺-S-(2-苯并咪唑基)钠(a～e)以及N,N'-二(芳磺酰)亚磺酰胺-S-(2-苯并咪唑基) (f～i)的合成. 通过在感光乳剂中的应用,我们发现a,b,和c具有超增感作用, 它们分别使卤化银乳剂的感光度提高62％ , 22％ 和 45％.     

新型高分子手性固定相的制备

酒石酸N,N′-二烯丙基酰胺与异氰酸酯反应得到对应的手性衍生物(3a~3c)。3在丙烯酰化硅胶表面发生自由基聚合反应,得到用于高效液相色谱柱的新型高分子手性固定相。3及其手性固定相的结构经1HNMR,IR和元素分析表征。     

N,N′-二(芳磺酰)亚磺酰胺-S-(2-苯并咪唑基)类化合物的合成

本文报道了新化合物N,N＇—二(芳磺酰)亚磺酰胺—S—(2—苯并咪唑基)钠(a～e)以及N,N＇—二(芳磺酰)亚磺酰胺—S—(2—苯并咪唑基)(f～i)的合成。通过在感光乳剂中的应用,我们发现a,b和c具有超增感作用,它们分别使卤化银乳剂的感光度提高62％,22％和45％。 钠—N—氯芳磺酰亚胺化合物既是一类精细化工产品,又是一类重要的反应中间体。由它们     

有机磷化合物的研究 XXV: 由N,N''-取代亚烷基双酰胺合成α-氨基膦酸

报导了亚磷酸三苯酯与对称的N,N'-烷撑二碳酰胺或N-羟在碳酰胺的反应后经水解合成α-氨基膦酸的新方法, 反应机理包括有二碳酰胺对三价磷的亲电进攻.     

简单亚胺的高效烯丙基化反应研究

首次实现了In(OTf)3催化下二丁基二烯丙基锡对活性较低的简单亚胺的高效烯丙基化加成. 烯丙基锡试剂和亚胺底物在10 mol%的In(OTf)3催化下, 无需添加其它辅助试剂, 二氯甲烷中室温搅拌10 h, 就可以得到收率为80%～99%的高烯丙基胺产物. 用四烯丙基锡替换该体系中的二丁基二烯丙基锡, 50 mol%用量即能得到很好的结果. 同时还对反应的机理进行了探讨.     

N，N’-二芳基硫代草酰胺与1，2-二溴乙烷的反应的研究

以N,N'-二芳基二硫代草酰胺与1,2-二溴乙烷进行S烷基化反应,合成了一系列2,3-双芳基亚氨基-1,4-二硫杂环己烷,反应在4h内完成,产率52%～62%.产物结构经元素分析,IR,1HNMR及MS表征,并以单晶X射线衍射分析进一步确证.     

烯丙基二异雪松基硼烷的制备及其与羰基化合物的不对称反应

本文以(-)-α-雪松烯为原料, 制备了烯丙基二异雪松基硼烷(Icd~2B-CH~2CH=CH~2). 该手性硼烷很容易与醛反应生成相应的烯丙基取代的手性仲醇, 光学产率在60%e.e.左右. 与潜手性酮反应的光学产率低于30%e.e..     

苯并[e][1,2,3]噁噻嗪-2,2-二氧化物的烯丙基化反应研究

探索了锡粉促进下苯并[e][1,2,3]噁噻嗪-2,2-二氧化物与烯丙基溴的烯丙基化反应.研究结果表明:各种底物都能顺利发生烯丙基化反应并且产物产率高;当用烯丙基溴衍生物进行反应时,得到的都是γ-加成产物.该烯丙基化反应产物在碱的促进下可发生N-烯丙基化反应,得到苯并[e][1,2,3]噁噻嗪-2,2-二氧化物的双烯丙...     

异氰酸酯的反应

我们研究了芳基和烷基异氰酸酯在消耗性镁阳极存在下的有机电解反应。芳基异氰酸酯电解得N, N'-二取代脲, 烷基异氰酸酯则还原偶联为N, N'-二取代草酰胺。我们认为这是由于烷基异氰酸酯从阴极得到电子发生比分子偶联, 芳基异氰酸酯则是与阴极析出的高分散的活性镁起作用。     

新轴手性N,N-Dioxide Biscarbolin衍生物催化酮亚胺的不对称硅氢化反应

以L-色氨酸为原料合成了5个伯酰胺结构的轴手性双咔啉N—O催化剂N2,N2'-二氧-9,9'-二甲基-3,3'-取代甲酰胺-β-双咔啉(4A~4E),并用于不对称催化酮亚胺的还原反应.结果表明,催化剂的催化转化率较高(80%~98%),立体选择性(e.e.值)较好,其中催化剂N2,N2'-二氧-9,9'-二甲基-3,3'-环己基甲酰胺-β-双咔啉(4B)的催化转化率达到了98%,e.e.值达68%.     

复杂高铋物料中铅的Na2EDTA滴定法测定

复杂高铋物料中,铋、砷、锑、锡四元素含量高且共存时会影响铅的测定。特别是铋含量高时对铅的测定影响大。实验用EDTA—酒石酸联合掩蔽铋、砷、锑、锡,在稀硫酸介质中以硫酸钾为沉淀剂,使铅生成硫酸铅钾复盐沉淀而与铋、砷、锑、锡、铁、铜、锌、铝、钴、镍等干扰离子分离,沉淀以乙酸-乙酸钠浸取,二甲酚橙为指示剂,Na2EDTA滴定法测定铅。试验进一步优化了测定条件,确定最佳条件：硫酸（1 1）加入量为7mL、硫酸钾用量为5g、煮沸时为5min、沉淀陈化时间为2h、EDTA 50g/L 加入量为10mL、酒石酸用量为0.5g,铅的回收率99.70% ～100.65%。将实验方法应用于测定复杂高铋物料中铅,标样BY0111-1与给定值一致,相对标准偏差（n=11）RSD 0.20%～0.23%,满足生产测试要求。     

同时溶解和ICP-AES同时测定铜基锡银焊料中的锡和银

提出了简单、快速地同时溶解及测定铜基锡银焊料中锡银的新方法.合金样品经2 g酒石酸和8 mL稀硝酸溶解后,用电感耦合等离子发射光谱仪法（ICP-AES）同时测定溶液中的锡和银.回收率为98%-102%,RSD为0.9%-2.1%.     

Analysis of tellurides of lead and tin by automatic titrations

An analytical method based on automatic potentiometric EDTA and redox titrations was developed for the analysis of tellurides of lead and tin.First, the sum of lead and tin is titrated at pH 4.5 by adding a known excess of EDTA and back-titrating with a standard lead solution. After addition of ammonium fluoride to mask the tin, the EDTA released from the Sn-EDTA complex is titrated with standard lead solution. Alternatively, after the determination of total lead and tin, lead may be determined by back-titration with standard lead on a separate sample aliquot using tartaric acid to mask the tin. Tellurium is separated as tellurous acid, which is then dissolved in a dilute sulfuric acid solution and oxidized by permanganate at room temperature; the excess permanganate is back-titrated with iron(II) solution automatically. This titration may also be used to determine tellurium in the presence of lead and tin after treatment with perchloric acid. Accuracies of 0.1-0.2% can be obtained.     

Na2EDTA滴定法测定粗二氧化碲中铅含量

建立了用氢溴酸消除锑、砷、锡干扰,用硫酸将铅形成硫酸铅沉淀,再用EDTA络合滴定法测定粗二氧化碲中铅量的方法。试样用硝酸、盐酸溶解,用硫酸沉淀铅,氢溴酸消除锑、砷、锡的干扰后,过滤分离其他共存元素,以乙酸-乙酸钠缓冲溶液溶解硫酸铅沉淀,在pH=5.0～6.0时,以二甲酚橙作指示剂,用Na_2EDTA溶液滴定溶液中铅含量。实验结果表明,氢溴酸加入量为15mL,酒石酸加入量为10mL,沉淀体积为50～60mL,沉淀时间1h以上时,方法相对标准偏差(RSD)在0.10%～1.1%,加标回收率为97.1%～102%,满足粗二氧化碲中铅量的生产控制检测要求。     

Determination of tin in ores, iron, steel and non-ferrous alloys by atomic-absorption spectrophotometry after separation by extraction as the iodide

A simple and moderately rapid method for determining 0.001% or more of tin in ores, concentrates and tailings, iron, steel and copper-, zinc-, aluminium-, titanium- and zirconium-base alloys is described. After sample decomposition, tin is separated from the matrix elements, except arsenic, by toluene extraction of its iodide from a 3M sulphuric acid-1.5M potassium iodide medium containing tartaric and ascorbic acids. It is finally back-extracted into a nitric-sulphuric acid solution containing hydrochloric acid to prevent the formation of an insoluble tin-arsenic compound and the resultant solution is evaporated to dryness. Tin is subsequently determined by atomic-absorption spectrophotometry in a nitrous oxide-acetylene flame, at 235.4 nm in a 10% hydrochloric-0.5% tartaric acid medium containing 250 mug of potassium per ml. Co-extracted arsenic does not interfere. Results obtained by this method are compared with those obtained spectrophotometrically with gallein after the separation of tin by iodide extraction.     

不完全抑制电导检测离子色谱法测定饮料中的苹果酸

采用一种抑制型离子色谱检测技术－－不完全抑制电导检测,以０．７５ｍｍｏｌ／ＬＮａ２ＳＯ４＋ＮａＯＨ（ｐＨ＝１１．５）为淋洗液对弱酸根离子如苹果酸、酒石酸等进行了测定,得到苹果酸、酒石酸的检测限分别为１．３１ｍｇ／Ｌ、３．０４ｍｇ／Ｌ;在２００ｍｇ／Ｌ以下相关系数分别为０．９９９８、０．９９９９;;各离子峰高的相对标准偏差（ＲＳＤ）分别为０．５７％、１．６０％。上率为９７．７￣１０４％。常见的强酸离     

Direct chiral resolution of tartaric acid by ion-pair capillary electrophoresis using an aqueous background electrolyte with (1R,2R)-(-)-1,2-diaminocyclohexane as a chiral counterion

Chiral resolution of native DL-tartaric acid was achieved by ion-pair capillary electrophoresis (CE) using an aqueous-ethanol background electrolyte with (1R,2R)-(-)-1,2-diaminocyclohexane (R-DACH) as a chiral counterion. Factors affecting chiral resolution and migration time of tartaric acid were studied. By increasing the viscosity of the background electrolyte and the ion-pair formation, using organic solvents with a lower relative dielectric constant, resulted in a longer migration time. The optimum conditions for both high resolution and short migration time of tartaric acid were found to be a mixture of 65% v/v ethanol and 35% v/v aqueous solution containing 30 mM R-DACH and 75 mM phosphoric acid (pH 5.1) with an applied voltage of -30 kV at 25 degrees C, using direct detection at 200 nm. By using this system, the resolution (Rs) of racemic tartaric acid was approximately 1. The electrophoretic patterns of tartaric and malic acids suggest that two carboxyl groups and two hydroxyl groups of tartaric acid are associated with the enantioseparation of tartaric acid by the proposed CE method.     

Reduction of tin and germanium to hydrides for determination by inductively-coupled plasma atomic emission spectrometry

The effect of a range of acids on the reduction of tin and germanium to their hydrides in aqueous solutions by means of sodium tetrahydroborate(III) solution in a continuous flow system is investigated. Interference effects in hydrochloric acid and tartaric acid reaction media are tabulated. Tartaric acid decreases many interference effects. Detection limits for both elements are low (ca. 0.2 μg l^-1) and the linear calibration ranges span nearly four orders of magnitude.     

Herstellung von Hilfsstoffen für die asymmetrische Synthese aus Weinsäure. Addition von Butyllithium an Aldehyde in chiralem Medium

Preparation of Auxiliaries for Asymmetric Syntheses from Tartaric Acid. Additions of Butyllithium to Aldehydes in Chiral Media. Chiral derivatives of the complexing 1,2-diheterosubstituted ethanes A–D are prepared from tartaric acid. The key starting materials are the succinic acid derivative 1 , the dioxolane 2a , and the diamide 3a . These are converted to the ethers, alkoxyamines, and alkylthio-amines listed in the first column of Table 2 which also contains the derivatives 21c, 22d , and 23d made from lactic acid, malic acid, and proline, respectively. It is shown that the highest optical yields (up to 40%) in reactions of butyllithium with aldehydes are obtained when mixtures of (?)-1,2,3,4-tetramethoxy-butane ( 4b ), (+)-2,3-dimethoxy-N,N,N′,N′-tetramethyl-1,4-butanediamine ( 17a ), and (?)-1,4-dimethoxy-N,N,N′,N′-tetramethyl-2,3-butanediamine ( 14c ) with pentane are used at temperatures down to ?150° and ratios of auxiliary/butyllithium of up to 10:1 (see equation (1), Tables 2–4).     

Kinetic study of the tartaric acid-periodate reaction: Determination of tartaric acid using an improved periodate-selective electrode

The preparation of an improved liquid-membrane periodate-selective electrode is described. The electrode exhibits rapid and near-Nernstian response in the range 2 × 10⁻⁶-10⁻² M. The electrode was used to monitor the course of the tartaric acid-periodate reaction. A potentiometric reaction rate method for the rapid and accurate determination of tartaric acid has been developed. A total of 0.4–120 μmol of tartaric acid has been determined with relative error of about 2.0%. The method has been applied to the determination of tartaric acid in pharmaceutical preparations and to the determination of small amounts of tartaric acid in impure citric acid.