吖啶橙—罗丹明6G—罗丹明B组合成各种混合染料体系的能量转移研究

本文对吖啶橙－罗丹明６Ｇ－罗丹明Ｂ组合成各种混合染料体系的能量转移进行了研究。结果表明，在十二烷基硫酸钠的水溶液中，吖啶橙－罗丹明６Ｇ间，罗丹明６Ｇ－；罗丹明Ｂ间，吖啶橙－罗丹明Ｂ间均能发生有效的能量转移。可以认为不仅染料单体，而且二聚体也是能量转移效率的竞争，探讨了表面活性剂对能量转移的影响。本文的工作将有助于拓宽能量转移的理论研究和应用范围。     

食品及生物样品中痕量草酸的荧光动力学法测定

拟定了一个荧光动力学测定痕量草酸根的新方法。在硫酸介质中，草酸催化重铬酸钾氧化罗丹明６Ｇ使其荧光猝灭。方法线性范围为０．８－１４．０ｍｇ／Ｌ，直接用于菠菜，人尿中草酸根的测定，获得满意结果。     

镉—碘化钾—罗丹明6G水明荧光体系的研究

本文首次将罗丹明６Ｇ应用于镉的荧光熄灭法测定，由于体系中加入β－环糊精后稳定性大大改变，克服了罗丹明类试剂常用的萃取体的一些缺点。在加入Ｈ３ＰＯ４、碘化钾－抗坏血酸、β－环糊精和罗丹明６Ｇ后，可在水相中直接用荧光法测定镉，方法灵敏，线性范围为０～６μｇ／２５ｍｌ常见离子中Ｂｉ＾３＋，Ｐｄ＾２＋，Ｈｇ＾２＋干扰测定，可应用于经分离后岩矿试样中镉的测定和环境水样中镉的直接测定。     

荧光动力学光度法同时测定硝酸根及亚硝酸根的研究

基于亚硝根对溴酸钾氧化罗丹明６Ｇ的催化及锌粉使硝酸根还原为亚硝酸根的原理，建立了同时测定亚硝酸根和硝酸根的荧光动力学法，用于饮用水、质控水样、饮料中硝酸根及亚硝酸根的测定，测定下限分别为０．０７４ｎｇＮＯ２＾－／ｍｌ和０．２５ｎｇＮＯ３＾－／ｍｌ。     

催化荧光法测定超痕量银的研究

基于在乙酸介质中，邻菲罗啉存在下，银对过硫酸钾氧化罗丹明６Ｇ具有催化作用，建立了催化荧光法测定超痕量银的新方法。方法的检出限为５．８０×１０＾－２μｇ／Ｌ，线性范围为２．００￣４０．００ｎｇ／２５ｍＬ。３０多种常见离子基本不干扰测定，将方法用于茶叶、阳极泥、水样中银含量的测定，结果满意。     

高磺酸钾—罗丹明6G催化荧光法测定超痕量钌

研究了在盐酸介质中,钌催化高碘酸钾氧化罗丹明６Ｇ的反应及动力学条件,建立了高灵敏测定超痕量钌的新方法。线性范围为０．２～１．０ｎｇ／２５ｍＬ,检出限为６．５×１０＾－１２ｇ／ｍＬ。方法已用于合成样中钌的测定。     

高碘酸钾-罗丹明6G催化荧光法测定超痕量钌

研究了在盐酸介质中,钌催化高碘酸钾氧化罗丹明６Ｇ的反应及动力学条件,建立了高灵敏测定超痕量钌的新方法。线性范围为０．２～１．０ｎｇ／２５ｍ Ｌ,检出限为６．５×１０－ １２ｇ／ｍ Ｌ。方法已用于合成样中钌的测定。     

催化荧光法测定痕量钼

本文拟定了一个催化荧光测定痕量钼的新方法，在磷酸介质中，钼（Ⅵ）催化过氧化氢氧化碘化钾的反应，其反应产物使罗丹明６Ｇ荧光猝灭。方法检出限１．２μｇ／Ｌ；线性范围２－１６μｇ／Ｌ。直接用于豆类、人尿中钼的测定及钼酸铅Ｋｓｐ的测定，获得满意结果。     

碘化物—碱性Che吨染料—聚乙烯醇体系高灵敏分光光度法测定铊

研究了在聚乙烯醇存在下，铊（Ⅲ）与碘化钾和罗丹明Ｂ，罗丹明６Ｇ、乙基罗丹明Ｂ、丁基罗丹明Ｂ碱性Ｃｈｅ吨染料形成离子缔合物的显色反应，讨论了铊（Ⅲ）－碘化钾－罗丹明Ｂ－聚乙烯醇体系的反应条件和分析特性，ε５８５＝７．０３×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，此法可用于水样中微量铊的测定。     

α—羰基烯酮环二硫代缩醛化学（XXXVI）：β,β—1,3—亚丙二硫基…

以β，β－１，３－亚丙二硫基－α，β－不饱和芳酮２与烯丙基或苄基Ｇｒｉｇｎａｒｄ试剂可选择性地进行１，２－加成得醇３、４，在硅胶Ｇ的催化下，醇３、４可分解生成β，γ－不饱和芳酮５、６。并对该分解反应的机制进行了初步探讨。     

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.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

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.     

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.     

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.     

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.