锌—水杨基荧光酮—酒石酸盐—表面活性剂四元混配型胶束络合物的分光光度法

１引言本文研究了Ｚｎ－水杨基荧光酮（ＳＡＦ）－酒石酸盐－阳离子表面活性剂（ＣＴＭＡＢ）四元混配络合物体系的光度法特性及分析应用，结果表明，该体系ε值为１．４７×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，线性范围０～４００μｇ／Ｌ的锌，用所拟方法在掩蔽剂存在下，于水相中直接测定了标准样品及实物中的锌，结果满意。２实验部分２．１仪器与试剂锌标准溶液：按常规方法配制；１×１０－３ｍｏｌ／ＬＳＡＦ乙醇溶液；２％酒石酸钾钠溶液；１×１０－３ｍｏｌ／ＬＣＴＭＡＢ溶液；ｐＨ＝８．３０的硼砂－盐酸缓冲溶液。ＵＶ－２６５型…     

新试剂二溴甲基偶氮羧胂与锆显色反应的研究及其应用

在１．６ｍｏｌ／Ｌ盐酸介质中，锆与试剂二溴甲基偶氮羧胂（ＤＢＭＣＡ）形成１∶３的蓝色配合物，λｍａｘ＝６４０ｎｍ，表观摩尔吸光系数ε３．７×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，锆量在０～１５μｇ／２５ｍＬ范围内符合比耳定律。本法的优点是可在三倍量的铪存在下直接测定锆，且操作简便，反应快速，有较高的选择性。应用于铜合金中微量锆的测定，取得了令人满意的结果。     

阻抑-催化褪色光度法测定痕量锑(Ⅲ)

１ 引 言 测定Ｓｂ（Ⅲ）有ＫＢｒＯ３－甲基橙褪色光度法、荧光酮衍生物光度法、Ｓｂ（Ⅲ）－乙基罗丹明Ｂ和Ｓｂ（Ⅲ）－甲基橙－溴化十六烷基三甲铵（ＣＴＭＡＢ）络合光度法等，但诸方法的ε为 １０４～１０５Ｌ·ｍｏｌ－１·ｃｍ－１，灵敏度不高，操作较烦。实验表明：碱性介质中，Ｓｂ（Ⅲ）能阻抑 ＣＴＭＡＢ催化结晶紫（ＣＶ）碱褪色反应，由此建立了阻抑－催化褪色光度法测定痕量锑（Ⅲ）新方法（ε５９０＝２．０× １０７Ｌ·ｍｏｌ－１·ｃｍ－１）。该方法灵敏度高，操作简便，重现性好。２ 实验部分２．１ 主要试剂与仪器 …     

铝与溴代二甲氨基苯基荧光酮的多元配合物的光度研究

本文研究了在表面活性剂存在性，铝与溴代二甲氨基苯基荧光酮的显色反应。在弱酸性介质中，Ａｌ＾３＋ＢＤＭＡＦ－ＣＴＭＡＢ三元配合物在水浴加热至７０℃－８０℃时形成，其最大吸收波长为５７７ｎｍ，Ａｌ＾３＋：ＢＤＭＡＦ＝１：２，表观摩尔吸光系数为１．３４×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，表观稳定常数为７．４×１０＾５。在ＰＨ９．５－１０．５的氨性缓冲介质中，Ａｌ＾３＋－Ｆ＾－－ＢＤＭＡＦ－非离子表面     

安替比林基重氮氨基—2,4—二硝基苯与汞（Ⅱ）的显色反应及其应用

本研究了试剂安替比林基重氮氨基－２４－二硝基苯（ＡＰＤＮＢＴ）与汞的显色反应，在Ｔｗｅｅｎ－８０存在下和ｐＨ＝１０．２～１２．３的缓冲溶液中，ＡＰＤＮＢＴ与汞生成黄色络合物，其络合比为Ｈｇ∶ＡＰＤＮＢＴ＝１∶２，建立了以４４５ｎｍ为参比波长，５３８ｎｍ为测量波长的双波长分光光度法，其表观摩尔吸光系数为２．１×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，线性范围是０     

2,3,7—三羟基—9—[3,5—二溴—4—（2,4—二羟基）苯偶氮]苯基荧光酮的合 …

介绍了新试剂２,３,７－三羟基－９－「３,５－二溴－４－（２,４－二羟基）苯偶氮」苯基荧光酮（ＤＢＡＲＰＦ）的合成。通过元素分析、红外光谱和紫外光谱等方法测试,确定了该试剂的组成和结构。研究了试剂与一些金属离子显色反应的光度性质,建立了光度法测定微量锆（Ⅳ）的新方法。在０．６ｍｏｌ／Ｌ盐酸介质中,阳离子表面活性剂ＣＴＭＡＢ存在下,锆（Ⅳ）与ＤＢＡＲＰＦ形成稳定的１：４水溶性络合物,λｍａｘ＝５３８     

二安替比林邻溴苯基甲烷与锰显色反应研究

合成了新试剂二安替比林邻溴苯基甲烷（ＤＡＯＢＭ），研究了它和Ｍｎ（Ⅶ）的显色反应条件．在磷酸介质中，Ｍｎ（Ⅱ）存在下，ＤＡＯＢＭ和Ｍｎ（Ⅶ）生成橙色产物，λｍａｘ为４８０ｎｍ，ε为９．６６×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，锰含量在０．１－１．２μｇ／２５ｍＬ内符合比尔定律．方法用于食品中痕量锰的测定，结果满意．     

二溴苯羟基荧光酮荧光光度法测定微量锆

本文提出了一个锆－二溴苯羟基荧光酮（ＤＢＨＰＦ）－乳化剂ＯＰ荧光光度法测定微量锆的新体系，在０．５～１．２ｍｏｌ／Ｌ的ＨＣｌ介质中，锆与ＤＢＨＰＦ生成组化比为１：４的红色荧光性络合物，荧光强度与锆（Ⅳ）的浓度在０～１００μｇ／Ｌ呈线性关系，检出限为２．０μｇ／Ｌ。灵敏度高，高选择性好，用于瓷釉等样品中ＺｒＯ２的测定，获得满意的结果。     

微乳液的增敏作用研究—5－Br－PADAP分光光度测定锰（Ⅱ）

以含水量８０％的Ｏ／Ｗ型ＳＤＳ／正丁醇／正庚烷／水微乳液为介质，以５－Ｂｒ－ＰＡＤＡＰ为显色剂，分光光度测定Ｍｎ（Ⅱ）．表观摩尔吸光系数ε５７０＝１．０８×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，与相同含水量的ＳＤＳ胶束体系相比，测定灵敏度有显著提高，改善了实验条件．方法用于铝合金和茶叶中Ｍｎ（Ⅱ）的测定，结果令人满意     

Fe（Ⅲ）—TEA—5—Br—PADAP—H2O2体系中催化波的研究及其应用

在０．２ｍｏｌ·Ｌ＾－１ＮＨ４Ｃｌ－ＮＨ３·Ｈ２Ｏ底液中，（ｐＨ为９．２６），得到一个极为灵敏的Ｆｅ（Ⅲ）－ＴＥＡ－５－Ｂｒ－ＰＡＤＡＰ－Ｈ２Ｏ２配合吸附催化波，其峰电位为－０．７１Ｖ（ｖｓ．ＳＣＥ）。铁浓度在１．８×１０＾－１０￣５．４×１０＾－６ｍｏｌ·Ｌ＾－１范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究，证明是一种配合吸附催化波，并成功地应用于各类水样，钒催化剂中微量或痕量铁的     

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.