毛细管硅胶基质整体柱的制备及应用

硅胶基质整体柱具有很好的通透性，高通量，及在有机溶剂条件下稳定等优点，已应用于毛细管电色谱（CEC）和微柱高效液相色谱（μ-HPLC）。本文从分离模式的角度，对毛细管硅胶整体柱的制备方法及其应用加以系统综述。并展望了这一领域未来的发展趋势。     

溶胶-凝胶法制备毛细管硅胶整体柱的研究进展

毛细管硅胶整体柱作为一种新型的分离介质,在色谱领域显示出了强大的生命力。本评述介绍了溶胶-凝胶法制备毛细管硅胶整体柱的方法,重点分析了溶胶-凝胶法制备毛细管硅胶整体柱的影响因素,总结了近几年毛细管硅胶整体柱在高效液相色谱和电色谱中的应用。     

中国科学院兰州化物所色谱技术研究开发中心

中国科学院兰州化物所色谱技术研究开发中心是我国唯一从事研制、生产高效气相色谱柱、高效液相色谱柱、液相色谱填料以及相关产品的高科技企业。中心致力于我国色谱柱产业核心技术体系的发展,独创出国际领先的液相沉渍。原位一体化合成制备高效PLOT色谱柱技术:拥有先进的超净-静态制备高效WCOT色谱柱技术:在国内率先完成了球形硅胶色谱填料制备研究开发工作,研制开发出多种液相手性分析填料以及国内急需的专用色谱柱,创造出多项     

中国科学院兰州化物所色谱技术研究开发中心

<正>中国科学院兰州化物所色谱技术研究开发中心是我国唯一从事研制、生产高效气相色谱柱、高效液相色谱柱、液相色谱填料以及相关产品的高科技企业。中心致力于我国色谱柱产业核心技术体系的发展,独创出国际领先的液相沉溃、原位一体化合成制备高效PLOT色谱柱技术;拥有先进的超净-静态制备高效WCOT色谱柱技术;在国内率先完成了球形硅胶色谱填料制备研究开发工作;研制开发出多种液相手性分析填料以及国内急需的专用色谱柱;创造出多项     

新型碳纳米管色谱固定相制备的研究进展

碳纳米管（CNTs）作为一种新型的功能材料,具有优异的物理、化学和机械性能,已经在分析化学领域得到了广泛的关注和应用。通过填充法或原位化学气相沉积法,可制备CNTs气相色谱固定相;将CNTs沉积在硅胶微球或有机聚合物基质微球表面,可制备填充式CNTs液相色谱固定相;通过包埋共聚法将CNTs嵌入聚合物整体柱内,可制备毛细管CNTs液相色谱整体柱。本文主要综述了近年来CNTs（单壁碳纳米管和多壁碳纳米管）用于色谱固定相制备的研究现状,包括气相色谱及液相色谱,并对该领域今后的发展进行展望。     

中国科学院兰州化物所色谱技术研究开发中心

中国科学院兰州化物所色谱技术研究开发中心是我国唯一从事研制、生产高效气相色谱柱,高效液相色谱柱、液相色谱填料以及相关产品的高科技企业。中心致力于我国色谱柱产业核心技术体系的发展、独创出国际领先的液相沉渍、原位一体化合成制备高效PLOT色谱柱技术;拥有先进的超净-静态制备高效WCOT色谱柱技术;     

毛细管整体柱的制备技术及其应用进展

毛细管整体柱是以其制备相对简单无需烧结塞子,渗透性好,柱效高,低柱压等优点,成为目前备受关注的液相色谱固定相.它具有较好的重现性,可进行快速分离,已被应用于毛细管电色谱(CEC)和微柱高效液相色谱(μ-HPLC).本文主要介绍近几年毛细管整体柱的制备技术及其应用概况.     

序言

色谱柱是色谱分离分析的“心脏”，液相色谱技术的每一次重大进展都与分离固定相的突破密切相关。如上世纪70年代末期高效液相色谱技术的建立和90年代初期“灌流色谱”（Perfusion Chromatography）的发展都是基于多孔硅胶和“穿透孔”分离固定相的发展。近年来，基于特殊孔结构的1．5～2．0μm高强度复合材料的制备成功地催生了超高效液相色谱（UPLC）分离技术，而整体柱材料作为新一代的分离介质，已成为色谱领域广泛研究的前沿课题之一，并已经在样品预处理、手性分离、生物分离分析等领域获得十分广泛的应用。我国色谱研究工作者在多孔硅胶固定相、手性分离固定相、亲和色谱固定相和整体柱固定相等研究领域都取得了重大的进展，有些方面的研究工作已达到或领先于国际先进水平。     

高效制备液相色谱柱技术的研究进展

本文概述了高效制备液相色谱柱的柱型结构、填料以及柱填充方法等研究的最新进展,讨论了制备柱与分析柱的不同特征,对目前普遍使用的压缩型制备柱的类型、结构及填充方法作了较为全面的评述,总结比较了工业化制备色谱填料不同于分析色谱填料的特点,探讨了高效制备液相色谱柱技术的应用和发展前景.     

中国科学院兰州化物所色谱技术研究开发中心

<正>中国科学院兰州化物所色谱技术研究开发中心是我国唯一从事研制,生产高效气相色谱柱.高效液相色谱柱.液相色谱填料以及相关产品的高科技企业.中心致力于我国色谱柱产业核心技术体系的发展.独创出国际领先的液相沉渍。原位一体化合成制备高效PLOT色谱柱技术.拥有先进的超净——静态制备高效WCOT色谱柱技术.在国内率先完成了球形硅胶色谱填料制备研究开发工作.研制开发出多种液相手性分析填料以及国内急需的专用     

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.