钯(Ⅱ)对钒(Ⅴ)-锰(Ⅱ)-Tween-20-二安替比林-(间-羟基)-苯基甲烷体系显色反应的抑制作用及应用

在酸性介质中钯（Ⅱ）对Ⅴ（Ⅴ）－Ｍｎ（Ⅱ）－Ｔｗｅｅｎ－２０－ＤＡｍＨＭ体系显色反应有阻抑作 用，基于此建立了一种测定钯的动力学分析方法，并研究了该阻抑反应的动力学参数。方法 的线性范围为２０～２４０μｇ　Ｐｄ（Ⅱ）／Ｌ，检测限为８．４×１０－９ｇＰｄ（Ⅱ）／ｍＬ。该体系灵敏度高，稳 定性好，用于石钯渣和钯催化剂中把（Ⅱ）的测定，结果满意。     

钯（Ⅱ）对钒（V）—锰（Ⅱ）—Tween—20—二安替比林—（间—羟基）—苯基甲？…

在酸性介质中钯（Ⅱ）对Ｖ（Ｖ）－Ｍｎ（Ⅱ）－Ｔｗｅｅｎ－２０－ＤＡｍＨＭ体系显色反应有阻抑作用，基于此建立了一种测定钯的动力学分析方法，并研究了该阻抑反应的动力学参数。方法的线性范围为２０～２４０μｇＰｄ（Ⅱ）／Ｌ检测限为８．４×１０＾－９ｇＰｄ（Ⅱ）／ｍＬ。该体系灵敏度高，稳定性好，用于石钯渣和钯催化剂中钯（Ⅱ）的测定，结果满意。     

高灵敏催化光度法测定痕量锰的研究

研究了在ＨＡｃ－ＮａＡｃ介质中，１，１０－邻菲口罗啉存在下，痕量Ｍｎ（Ⅱ）催化高碘酸钾氧化偶氮胂Ⅲ的褪色反应及动力学条件，建立了测定痕量锰的新方法。本法检出限为６．１５×１０－９ｇ／Ｌ，线性范围为０．２～３．２μｇ／Ｌ，已成功用于茶叶、花生、黄豆及中药材枸杞、灵芝中锰的测定。     

一类新偶氮试剂的研究：Ⅴ.HQSAH催化荧光法测定Mn（Ⅱ）

基于Ｍｎ（Ⅱ）对试剂２－（８＇－羟基喹啉－５＇－磺基－７＇－偶氮基）－１－羟基－８－氨基一萘二磺酸（以下简称ＨＱＳＡＨ）分解反应的催化作用，提出了锰的荧光催化动力学分析新方法，其λｅｘ／ｅｍ＝２３０／４１５ｎｍ，适宜酸度范围为ｐＨ１１．０～１２．０，Ｍｎ（Ⅱ）含量在０～０．０８μｇ／ｍＬ呈线性关系，该法用于分析铸造铝合金中的痕量锰，效果良好。还初步探讨了反应机制，确定了反应动力学方程，测定了反应速率和活化能。     

高碘酸钾-酸性品红-NTA-DDMAA体系催化光度法测定良量锰

报道了以氨三乙酸为活化剂，以Ｎ－十二烷基二甲基铵基乙酸（ＤＤＭＡＡ）为增敏剂，高碘酸钾氧化酸性品红催化光度法测定痕量锰的新方法，在ＤＤＭＡＡ存在下，灵敏度提高了７倍（Ｍｎ２＋量为１．２～２．４μｇ／Ｌ）和１４倍（Ｍｎ２＋量为２．４～５．２μｇ／Ｌ），相对标准偏差为２．０％，检出限为１．４×１０－７ｇ／Ｌ，可用于茶叶中锰的测定。     

二安替比林对甲氧基苯基甲烷光度法测定锰

研究了二安替比林对甲氧基苯基甲烷（ＣＡｐＭＯＰＭ）与Ｍｎ的显色反应条件,在磷酸介质中,Ｍｎ（Ⅱ）存在下,ＤＡｐＭＯＰＭ与Ｍｎ（Ⅶ）生成黄色产物,λｍａｘ＝４５０ｎｍ,ε＝１．０４×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,锰含量在０－４００μｇ．Ｌ＾－１内符合比耳定律,体系灵敏度高,稳定性好,用于茶叶和水样中锰的测定,结果满意。     

二安替比林对二甲氨基苯基甲烷-高碘酸钾催化光度法测定痕量钌

在磷酸介质和加热条件下,钌（Ⅲ）对高碘酸钾氧化二安替比林对圩甲氨基苯基甲烷（ＤＡＭＡＭ）的显反色应脸强催化作用,建立了催化动力学光度法测定痕量钌的新。方法的线性范围为０－５．４μｇ／Ｌ;检出限为２．１６＊１０＾－８ｇ／Ｌ;对２μｇ／Ｌ的Ｒｕ（Ⅲ）测定的ＲＳＤ为２．２９％（ｎ＝１１）。催化反应的表观活能为９２．２３ｋＪ／ｍｏｌ。考察了４０多种共存离子的影响。大多数常见离子不干扰测定。本法已用于矿样中     

萃取阻抑动力学光度法测定痕量镍

研究了在ｐＨ５．５的弱酸性介质中，利用镍（Ⅱ）阻抑邻菲罗啉活化铜（Ⅱ）催化过氧化氢氧化邻氨基酚的指示反应，用萃取手段控制反应时间、建立了萃取阻抑动力学光度法测定镍的新方法。方法的线性范围为１．０￣８０μｇ／Ｌ；检测限为９．１×１０＾－７ｇ／Ｌ。用于环境水样，铝合金和人发中镍的测定，结果满意。对反应机理谱进行了探讨。     

新阻化动力学光度法测定痕量铜

１引言我们在实验中发现，铜（Ⅱ）抑制Ｍｎ（Ⅱ）催化铬（Ⅵ）与二安替比林基对氯苯基甲烷（ＤＡＰＣＭ）的显色反应，从而建立了一种新的测定铜（Ⅱ）的阻化动力学方法。该法灵敏度高，选择性较好，线性范围较宽，稳定时间长，操作简便。用于粗铅和铝合金中铜的测定，结果满意。２实验部分２．１主要仪器和试剂７２２型光栅分光光度计（山东高密分析仪器厂）；５０１型超级恒温器（江苏实验仪器厂）。铬（Ⅵ）标准溶液：１．０ｇ／Ｌ和１．０ｇ／Ｌ；铜（Ⅱ）标准溶液：１．１０ｇ／Ｌ和１．０ｍｇ／Ｌ；０．２％（Ｗ／Ｖ）ＤＡＰＣＭ溶液…     

Triton X-100增溶动力学光度法测定痕量锰(Ⅱ)

１引言催化光度法测锰多为以Ｍｎ（Ⅱ）离子催化氧化水溶性染料褪色或增色为主，即所使用的指示反应的反应物或产物必须是均相体系，如为难溶物质，不能直接在水相测定，此时，若加入表面活性剂，利用表面活性剂的增溶效果，将非均相体系转变为拟均相体系便可实现水相直接测定。１－（２－吡啶偶氮）－２－萘酚（ＰＡＮ）为难溶物质，以ＴｒｉｔｏｎＸ－１００为增溶剂，在ＨＡｃ－ＮａＡｃ介质中，利用痕量Ｍｎ（Ⅱ）催化高碘酸钠氧化ＰＡＮ褪色反应建立了测定痕量锰的方法。２实验部分２．１试剂及仪器１ｇ／Ｌ的锰标准溶液；醋酸－醋酸钠…     

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.