铟（Ⅲ）—2—硫基苯骈噻唑—7—碘—8—羟基喹啉—5—磺酸三元络合物吸附波研究

在ＨＣｌ－ＮａＡｃ介质（ｐＨ２．５）中，用单扫示波极谱法可获得高灵敏的Ｉｎ（Ⅲ）－２－巯基苯骈噻唑（ＭＢＴ）－７－碘－８－羟基喹啉－５－磺酸（Ｆｅｒｒｏｎ）三元络合物吸附波，峰电位在一－０．６４Ｖ（ｖｓ．ＳＣＥ），峰电流与铟浓度在７．０×１０＾－１０ｍｏｌ／Ｌ～８．８×１０＾－７ｍｏｌ／Ｌ之间呈线性关系，检出限可达３．０×１０＾－１０ｍｏｌ／Ｌ，测得电活性络合物的组成为Ｉｎ（Ⅲ）：ＭＢＴ：１∶１∶     

蒙脱土修饰电极上某些神经递质的电化学行为

采用不同电化学方法对神经递质多巴胺（ＤＡ）在蒙脱土修饰电极上的行为进行了研究，结果发现，蒙脱土修饰膜地ＤＡ有明显的富集作用。在ＰＨ７．４时，ＤＡ强烈地富集在蒙脱土膜内，并显示完成的伏安响应而抗坏血酸（ＡＡ）和ＤＡＲ的代谢产物３，４－二羟基苯乙酸（ＤＯＰＡＣ）则无任何响应。采用计时库仑法测定了ＤＡ在蒙脱土膜内的表观扩散系数为２．３×１０＾－９ｃｍ＾２／ｓ，并计算了异相速率常数为２．７×１０＾－６ｃｍ     

镓(Ⅲ)-芦丁体系的吸附伏安行为及其应用于镓(Ⅲ)的测定

对镓（Ⅲ）－芦丁体系在悬汞电极上的吸附伏安法作了研究,确字电极过程。在ＰＨ５．０的ＨＡｃ－ＮａＡｃ缓冲底液中用该体系的１．５阶微分吸附伏安法测定镓,其线性范围是１＊１０＾－１０－１＊１０＾－７ｍｏｌ／Ｌ;检测限为７．５＊１０＾－１１ｍｏｌ／Ｌ。用此法测定了粮食中的镓。     

铟(Ⅲ)-7-(1-苯偶氮)-8-羟基喹啉-5-磺酸钠的配位吸附波及其应用

在ｐＨ４．５的 ０．０１５ ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ介质中，Ｉｎ铟（Ⅲ）－７－（１－苯偶氮）－８－羟基喹啉－５－磺酸钠（ＢＱ）在滴汞电极上于－０．６６５－０．７０ Ｖ（ｖｓ．ＳＣＥ）电位处得到络合物的吸附还原波，其一阶导数峰电流Ｉ＇ｐ与Ｉｎ（Ⅲ）浓度在４．０× １０~（－８）～３．５ × １０~（－６）ｍｏｌ／Ｌ范围内呈良好的线性关系，检测限为１．６ × １０~（－８）ｍｏｌ／Ｌ Ｉｎ（Ⅲ）．应用该法测定了铅粉和氢氧化铝样品中的微量铟，结果令人满意。对电极反应机理进行了探讨。     

新试剂7-(2,4-二羟基-5-羧基苯偶氮)-8-羟基喹啉-5-磺酸与铝的荧光反应性能的研究

研究了新试剂７－（２,４－二羟基－５－羧基苯偶氮）－８－羟基喹啉－５－磺酸（简称ＤＨＣＢＡＱＳ）与铝（Ⅲ）形成的络合物的荧光性能。在ｐＨ４．６２的ＮａＡｃ－ＨＡｃ体系中形成１∶１型强荧光配合物,其λｅｘ＝５１０ｎｍ、λｅｍ＝５７２ｎｍ,铝（Ⅲ）含量在０～０．０８ｍｇ／Ｌ范围内与荧光强度呈线性关系,方法检出限为１．０４×１０－１０ｍｏｌ／Ｌ。本方法用于茶叶、淀粉及水样中痕量铝（Ⅲ）的测定。     

吸附络合物体系的示波分析

Ｉｎ（Ⅲ）在ｐＨ４５７ＨＡｃＮａＡｃ０．１％ＶＣ０．０６％ＨＣｕＰ溶液中，用示波计时电位法可获得良好示波图，其切口电位为Ｅ＝０９０（Ｖｓ．ＳＣＥ），切口高度与Ｉｎ（Ⅲ）浓度在８００×１０－７～１４×１０－５ｍｏｌ／Ｌ范围内成正比，检出限可达５０×１０－７ｍｏｌ／Ｌ吸附络合物组成为Ｉｎ（Ⅲ）：铜铁试剂（ＨＣｕｐ）＝１∶１，条件稳定常数为５９×１０３     

偶氮氯膦Ⅲ—希土极谱络合吸附波的研究

在０．０６ｍｏｌ／Ｌ ＮａＡｃ－ＨＡｃ ｐＨ４．５的缓冲底液中，偶氮氯膦Ⅲ（ＣＰＡⅢ）在－０．２５Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ）有一良好的微分脉冲极谱还原波，加入希土（ＲＥ）后期峰高电流（ｉｐ）降低，轻希土浓度在１×１０＾－６～６×１０＾－６ｍｏｏ／Ｌ，钇和重希土浓度在２×１０＾－７～３×１０＾－６ｍｏｌ／Ｌ范围中，ｉｐ的降低与浓度呈线性关系，表明ＣＰＡⅢ亦是可用的希土极谱分析试剂。实验证明它们是不可     

Keyword Index Vol. 7, 1996

ＫｅｙｗｏｒｄＩｎｄｅｘＶｏｌ．７，１９９６￥／／Ｑ，ａ－Ｄｉｏｘｏ（ｅｓｔｅｒ）ｋｅｔｅｎｅ（－）１０－ＥＰＩ－ａ－－ｃｙｐｅｒｏｎｅｄｉｅｎｅ（７Ｏ３）ｃｙｃｌｅｄｉｔｈｉｏａｃｅｔａｌｓ（６９５）２－ＢｅｎｚｅｎｉｍｉｄａＺｏｌｅｔｈｉｏｌ（９...     

镓,铟与酸性铬深蓝络合物吸附波的研究及其应用

在醋酸盐缓冲溶液中，用单扫示波极谱法分别获得了镓（Ⅲ）、铟（Ⅲ）与酸性铬深蓝灵敏的络合物吸附波。两个波的峰电位分别为－０５１Ｖ和－０６３Ｖ（ｖｓＳＣＥ），镓（Ⅲ）的线性范围为７２０×１０－７～７４６×１０－６ｍｏｌ／Ｌ；铟（Ⅲ）为１７４×１０－７～４８８×１０－６ｍｏｌ／Ｌ。作者研究了该电极反应机理。该法用于矿石中镓、铟的测定，结果满意。     

镓(Ⅲ)-向红菲咯啉络合物极谱吸附波的研究及应用

在 ＰＨ＝４．２的 ０．０７ ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ介质中，Ｇａ（Ⅲ）－向红菲咯啉络合物在单扫描极谱仪上于－０．９８ Ｖ（ｖｓ．ＳＣＥ）处产生一灵敏的吸附还原波，其二阶导数波灵敏度高，波形好，峰电流 Ｉｐ与 Ｇａ（Ⅲ）在 ８．０×１０－８～３．０× １０－６ｍｏｌ／Ｌ的浓度范围内呈现良好线性关系，检出限为７．０×１０－８ｍｏｌ／ＬＧａ（Ⅲ）。用该法对粮食中的镓进行了测定，并对电极过程进行了研究。     

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.