新体系Fe（Ⅲ）—KIO4—偶氮氯膦Ⅲ催化动力学光度法测定食品痕量铁的…

研究了在硫酸介质中，痕量Ｆｅ（Ⅲ）催化高碘酸钾氧化氮氯膦Ⅲ的褪色反应及其动力学条件。本法检测限为８．７８×１０＾－９ｇ／Ｌ，测Ｆｅ（Ⅲ）范围０－１．４μｇ／１０ｍＬ，采用巯基葡聚糖凝胶分离富集，使本法选择性大大提高，建立了一种高灵敏、高选择测定痕量Ｆｅ（Ⅲ）的新方法，用于食品中痕量Ｆｅ（Ⅲ）的测定，结果满意。     

停流流动注射—动力学方法多组份同时测定的研究：铁（Ⅱ）,钛（Ⅲ）和…

依据诱导反应原理，提出了同时测定多组份的动力学方法，并以停流流动注射分析研究了Ｆｅ（Ⅱ），Ｔｉ（Ⅲ）及Ｖ（Ⅳ）诱导的Ｃｒ（Ⅵ）－Ｉ＾－反应体系，建立了铁，钛和钒同时测定的条件。对铁，钛和钒测定的线性范围分别为０－２．２μｇ／ｍｌ，０－３．１μｇ／ｍｌ及０－１．８μｇ／ｍｌ，检测限分别为０．０１２，０．０２０和０．０１８μｇ／ｍｌ。     

巯基葡聚糖凝胶分离富集催化光度法测定痕量铁（Ⅲ）

研究了在硫酸介质中Ｆｅ（Ⅲ）催经抗坏血酸、溴酸钾和对氯偶氮氯膦之间的褪色反应及动力学条件，建立了学光度法测定痕量Ｆｅ（Ⅲ）的新方法，其灵敏度为１．６×１０＾－９ｇ／Ｌ；建立范围为Ｆｅ（Ⅲ）０－０．１２ｍｇ／Ｌ，采用巯基葡聚糖凝胶分离干扰离子，使方法的选择性有很大的提高，已用于食品和人发中Ｆｅ（Ⅲ）的测定，结果令人满意。     

催化动力学吸光光度法测定污水中痕量汞

研究了亚铁氰化钾－硫脲－硫酸测定痕量汞的催化显析体系。检出限为３ｎｇ．ｍｌ＾－１，Ｈｇ（Ⅱ）浓度在０－１．０μｇ／２５ｍｌ范围内遵守比耳定律，摩尔吸光系数为６．６×１０＾５，回收率为９９．０％－１１０．３％，相对标准偏差２．７７％，方法可直接测定污水中纳克量的Ｈｇ（Ⅱ），结果令人满意。     

偶合反应化学发光法测定痕量银的研究——K4Fe（CN）6—Luminol体系

将Ａｇ（Ｉ）催化Ｋ４Ｆｅ（ＣＮ）６的水合反应与Ｌｕｍｉｎｏｌ同Ｃｕ（ＣＮ）＾２－４的化学发光反应相偶合，建立起一种新的灵敏测定痕量银的化学发光分析法，在所研究的优化条件下，该法测定银的选择性较好，检测限达到４．０×１０＾－１３ｇ／ｍＬＡｇ线性浓度范围为１．０×１０＾－１２～１．０×１０＾－６ｇ／ｍＬＡｇ对４×１０＾－１１ｇ／ｍＬＡｇ（Ｉ）溶液连续１１次测定的ＲＳＤ≤３．５％，用于环境水和岩矿中银的     

催化动力学光度法测定痕量钼的研究

研究了在氨水介质中钼（Ⅵ）催化过氧化氢氧化噻嗪红Ｒ的褪色反应其动力学条件，建立了一种高灵敏，高选择性测定食品和水中痕量钼（Ⅵ）的新方法，可测定０．０１－１．０μｇ／２５ｍｌ范围内的钼（Ⅵ），方法当敏度为６．４×１０＾－＾１＾０ｇ／ｍｌ。     

催化褪色反应动力学法测定痕量钯

基于弱酸和α，α′－联吡啶介质中，Ｐｄ（Ⅱ）强烈催化氧化氢氧化中性红褪色反应，建立了动力学光度法测定痕量Ｐｄ（Ⅱ）新方法，方法检出限为０．７１ｍｇ．ｍｌ＾－１，线性范围为０～０．６μｇ／２５ｍｌ，可用于矿样中钯的测定。ｇ     

新体系Fe（Ⅲ）－KIO＿4－偶氮氯磷Ⅲ催化动力学光度法测定食品中痕量铁的研究

研究了在硫酸介质中，痕量Ｆｅ（Ⅲ）催化高碘酸钾氧化氨氯磷Ⅲ的褪色反应及其动力学条件。本法检测限为８．７８×１０￣（０９）ｇ／Ｌ，测Ｆｅ（Ⅲ）范围０～１．４μｇ／１０ｍＬ，采用硫基葡聚糖凝胶分离富集，使本法选择性大大提高，建立了一种高灵敏、高选择性测定痕量Ｆｅ（Ⅲ）的新方法，用于食品中痕量Ｆｅ（Ⅲ）的测定，结果满意。     

催化动力学光度法测定痕量Cr（Ⅲ）

在弱酸性介质中,以２,２‘－联吡啶作活化剂,Ｃｒ（Ⅲ）强烈论过氧化氢氧化中性红褪色反应,催化反应的表观活化能为４９．８８ｋＪ·ｍｏｌ＾－１。据此建立了测定痕量Ｃｒ（Ⅲ）的催化动力学光度法。方法的检出限为２ｎｇ·ｍｌ＾－１,线性范围为０￣０．１μｇ·ｍｌ＾－１。通过测定模拟 １、矿井水样及电镀废水样中痕量Ｃｒ（Ⅲ）,结果满意。     

反相离子对液相色谱分离—柱后衍生化学发光检测痕量金…

报道了反相离子对液相色谱－柱后衍生化学发光检测方法分离测定痕量的钴（Ⅱ）、铁（Ⅱ）、铜（Ⅱ）、铁（Ⅲ）及铬（Ⅲ）。利用弱络合性的乳酸作为淋洗剂，加入适量的十二烷基磺酸钠作对离子试剂，研究了分离条件、发光条件及二者的匹配方式等因素对分离检测的影响。测定线性范围分别为（ｇ／ｍＬ）：Ｃｒ（Ⅲ）５．０×１０＾－９～１．０×１０＾－５；Ｆｅ（Ⅱ）２．０×１０＾－９～１．０×１０＾－５；Ｆｅ（Ⅲ）８．０×１０     

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%.     

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.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.