含烯丙基席夫碱ⅣB族的金属烯烃聚合催化剂的合成、结构、高分子化及其催化乙烯聚合反应

制备出两类含烯丙基席夫碱的ⅣB族配合物[R(N=CH-C₆H₃(3-R)O)₂MCl₂ (R=Allyl；R′=Pheny；M=Ti(6)，M=Zr(7)；R=tert-Butyl；R′=Allyl；M=Ti(8)；M=Zr(9))，配合物(7)的单晶结构显示围绕中心金属的配合构型为畸变八面体，其中2个氯原子处于顺式位置。配合物(7，9)中的烯丙基与苯乙烯共聚可得到高分子化烯烃聚合催化剂(PSC1；PSC2)。在助催化剂(MMAO)存在下，配合物9和相应的高分子化催化剂(PSC2)显示出很高的催化乙烯聚合的活性。     

用MES及XRD研究FT合成催化剂的活性结构

采用穆斯堡尔谱及Ｘ光衍射法研究了共沉淀法制备的不同Ｆｅ／Ｍｎ比催化剂在焙烧、合成气还原及ＦＴ反应后体系相结构的变化。结果表明：锰助剂的加入使催化本相由铁磁性逐渐转化为超顺磁性，相应使催化剂还原逐渐难，Ｍｎ助剂促进了ＦＴ合成反应进行。反应性能与Ｆｅ／Ｍｎ尖晶石（Ｆｅ１－ｙＭｎｙ）３Ｏ４组成含量及式中ｙ大小密切相关，与ＭｎＣｏ３及ＭｎＯ的存在也有一定关系。富铁催化剂中Ｍｎ主要起电子助剂作用，而富锰催化     

纳米材料的特性及其在电催化中的应用

综述了纳米材料的表面效应，体积效应和Ｋｕｂｏ效应，并介绍了其在电催化反应听一些应用。     

铁基超细粒子催化剂结构与还原行为的Mossbauer谱研究

铁基超细粒子催化剂具有优良的F －T反应性。本工作利用原位Mossbauer谱辅以XRD技术研究了含有钾助剂的F－T合成铁基超细粒子催化剂的结构与还原行为，考察了催化剂组成和第二金属组分（Mn,Zn,Mg）的影响。“纯”铁超细粒子催化剂在氢气中很容易经Fe3O4还原为零价铁。第二金属组分的引入，一方面了阻碍了催化剂的还原，另一方面稳定了Fe^2 的存在而使其成为还原的主要中间相，这有利于反应条件下形成类晶石结构的活性相。对于Fe-Mn催化剂，上述效应随锰含量的增加而更趋显著。铁基超细粒子催化剂在氢气中还原能力依“纯”Fe>Fe-Zn>Fe-Mn>Fe-Mg的顺序递减，这在一定程度上反映了铁与第二金属组分之间相互作用的强弱。     

高岭土催化剂中铝的测定

高岭土催化剂是目前石油化工工业中生产和使用的一种无机催化剂,它以高岭土和分子筛为主要原料,经加工而成.铝的含量(通常以Al_2O_ 3计)是该产品的必测项目之一.鉴于目前尚未制订出标准测定方法,现有文献资料也未找到一种能完全套用的方法,我们借鉴其它样品的试样分解方法和铝的测定方法,经试验提出了一个完整的铝含量的测定方法.1 试验部分1.1 主要试剂乙酸:50%过氧化氢:3?TA溶液:0.05mol·L~(-1)六次甲基四胺:30%二甲酚橙指示剂:0.2%     

金属茂催化剂及其聚烯烃的研究开发

本文在综述国外金属茂催化剂及工业化概况的基础上，报道了石油化工科学研究院从事烯烃聚合金属茂催化剂及用其制备聚烯烃的研究进展。已成功地开发出独特的制备线性低密度聚乙烯复合型金属茂、限制几何构复合型金属茂笔间规选择性复合型金属茂及将其负载化的专利技术。分别在石油化工科学研究院、扬子石化公司、兰州化学工业公司运用淤浆、本体、气相聚合工艺对所得负载型金属茂经烯烃聚合的催化性能进行评价。     

镧对磷钒催化剂性能的影响

镧对磷钒催化剂性能的影响李铭岫，王心葵，杨述韬，张志新，刘翠格，周敬来（河北师范学院化学系，石家庄０５００９１；中国科学院山西煤炭化学研究所，太原０３０００１）关键词镧，磷钒催化剂，正丁烷，选择，氧化，顺丁烯二酸酐磷钒系催化剂是正了烷氧化制顺丁烯二酸...     

手性催化剂的结构及其反应性能

以天然产物为前体对手性催化剂进行了分类，对每种手性催化剂列举了所催化的不对称反应及其对映选择性；并对催化剂的结构与反应性能的关系进行了初步的总结和分析。参考文献７０篇。     

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.