双氯灭痛与苯酯类试剂荷移反应的研究

本文研究了双氯灭痛与苯醌和四氯苯醌之间的荷移反应。实验结果表明：双氯灭痛与对苯醌和四氯苯醌的反应分别在乙醇介质和弱碱性介质中进行。配合物的最大吸收波长分别是５１０ｎｍ和３３５ｎｍ；表观摩尔吸光系数分别是１．２９×１０＾３和１．１×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１；比尔定律的线性范围分别是１０￣１２０μｇ／ｍＬ和２￣３０μｇ／ｍＬ。用拟定的方法分析药物制剂含量获得满意结果。     

双氯灭痛与苯醌类试剂荷移反应的研究

本文研究了双氯灭痛与对苯醌和四氯苯醌之间的荷移反应．实验结果表明：双氯灭痛与对苯醌和四氯苯醌的反应分别在乙醇介质和弱碱性介质中进行．配合物的最大吸收波长分别是５１０ｎｍ和３３５ｎｍ；表观摩尔吸光系数分别是１．２９×１０３和１．１×１０４Ｌ·ｍｏｌ－１·ｃｍ－１；比尔定律的线性范围分别是１０～１２０μｇ／ｍＬ和２～３０μｇ／ｍＬ．用拟定的方法分析药物制剂含量获得满意结果     

荷移反应用于氨苄青霉素的测定

研究了氨苄青霉素与对苯醌的荷移反应，确定了反应条件。在ＰＨ４．４－５．０的醋酸－醋酸钠缓冲溶液中形成１：１络合物，其λｍａｘ＝４７２ｎｍ。氨苄青霉素三水合物浓度在１０－１２５ｍｇ／Ｌ范围地线性关系；当浓度为５０ｍｇ／Ｌ时相对标准偏１．８％；表观摩尔吸光系数为２．６４×１０＾３Ｌ．ｍｏｌ＾－１．ｃｍ＾－１。应用拟定的方法测定药物制剂含量，结果与药典方法一致。回收率在９６％以上。     

荧光分析法测定痕量丁二酮

本文报道了邻苯二胺与丁二酮在１ｍｏｌ／ＬＨ２ＳＯ４介质中反应生成２，３－二甲基喹喔啉。该化合物具有较强的荧光（λｘ／λｅｍ＝３４０ｎｍ／４９０ｎｍ）其荧光量子产率ΦＦ＝０．１０１。丁二酮浓度在４．０×１０＾－７～５．２×１０＾－５ｍｏｌ／Ｌ范围内与转化成产物的相对荧光强度呈线性关系，相对标准偏差为１％，检出限为１．３×１０＾－７ｍｏｌ／Ｌ，考察了３０种物质表明，该法选择性好，用于实际啤酒样品中丁二     

银微盘电极上头孢氨苄降解产物的伏安行为及其应用

基于头孢氨苄降解产物中含有巯基，能与Ａｇ＾＋生成难溶化合物的特性，在银微盘电极上研究了ＣＥＸ降解产物的伏安行为，探讨了电极反应的机理。运用示差脉冲溶出伏安法，在０．１ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ介质中，ＣＥＸ降解产物的还原峰电流与ＣＥＸ浓度于８．０×１０＾－８－７．０×１０＾－６ｍｏｌ／Ｌ范围内呈良好线性关系；检测限为１．０×１０＾０８ｍｏｌ／Ｌ；测定了头孢氨苄胶囊中ＣＥＸ含量为９２．０％，与药典     

2—羟基—3—羧基—5—碘酸基苯基重氮氨基偶氮苯与铊反应的分光光度法…

于ｐＨ１０．０－１１．０的ＮＨ３－ＮＨ４Ｃｌ缓冲介质中，在ＴｒｉｔｏｎＸ－１００存在下，铊与２－羟基－３－羧基－５－磺酸基苯基重氮氮基偶氮苯形成组成比为１：３的红色配合物，其最大吸收波筏和对比度分别为５１０ｎｍ和８０ｎｍ，表观摩尔吸光系数为１．５２×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，线性范围为０－０．７０ｍｇ／Ｌ，室温下显色反应立即完成，配合物至少稳定２ｈ。方法用于水样，烟叶和煤灰中痕量铊的分     

5′—硝基水杨基荧光酮分光光度测定微量碲

在ｐＨ４．１～４．６乙酸盐缓冲介质中，碲（Ⅳ）与５′硝基水杨基荧光酮（５′－ＮＳＦ）溴化十六烷基吡啶（ＣＰＢ）反应形成组成比为１：４；４的水溶性和稳定性皆佳的红色三元配合物，最大吸收波长为５４２ｎｍ，表观摩尔吸光系数为１．０２×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，桑德尔灵敏度是１．２５×１０＾－３μｇ．ｃｍ＾－２线性范围０～０．４０ｍｇ／Ｌ，据此提出了测定碲的灵敏，简便的分光光度分析新方法，直接     

反向流动注射化学发光法测定痕量铁

基于邻菲别名林对高碘酸钾－碱性鲁米诺－铁体系发光强度的增敏作用建立了水体中总铁的反向流动性化学发光检测方法。该法线性范围在１×１０＾－４－１０ｍｇ／Ｌ，检测限为３×１０＾－６ｍｇ／Ｌ，对于５×１０＾－３ｍｇ／Ｌ Ｆｅ测定９次的相对标准偏差为０．９％。此方法已用在水处理中总铁的监测。     

阴离子表面活性剂—溴化十二烷基二甲基苄基铵—溴百里酚蓝显色反应…

本文研究了溴化十二烷基二甲基苄铵－溴百里酚蓝与阴离子表面活性剂显色反应的适宜条件结果表明，在ｐＨ７．４～８．２范围内阴离子表面活性剂与题示试剂形成１：２：１的绿色离子缔合物，其最大吸收峰位于６１４ｎｍ处。表观摩尔吸光系数分别为ε＾ＳＤＢＳ６１４＝３．９９×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１；ε＾ＳＤＳ６１４＝３．７０×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，ε＾ＳＬＳ６１４＝１．７１×１０＾４Ｌ．     

过氧化物模拟酶催化的苯基荧光酮氧化反应及其分析应用

在ＮＨ４Ｃｌ－ＮＨ４ＯＨ缓冲介质中，氯化血红素（Ｈｅｍｉｎ）有显著的过氧化物模拟酶活性，催化过程化氢氧化苯基荧光酮褪色。本文探讨了反应机理，比较Ｈｅｍｉｎ与天然酶催化性能，考察反应条件和共存物质影响，从而提出测定Ｈｅｍｉｎ和过氧化氢的高灵敏分光光度法，线性范围分别为０￣３．０×１０＾－８ｍｏｌ／Ｌ和０￣１．２×１０＾５ｍｏｌ／Ｌ；检测限（３σ）分别为１．８×１０＾－１０ｍｏｌ／Ｌ和１．４×１０＾７     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.