PdSAPO－5分子筛在甲醇转化反应中的催化性能及机理

用连续－脉冲激反应色谱评价了不同ＳＡＰＯ－５分子筛及一步法合成的ＰｄＳＡＰＯ－５催化剂对甲醇制烯烃（ＭＴＯ）反应的催化性能，用ＴＰＤ－ＭＳ及１３ＣＣＰＭＡＳＮＭＲ研究了其催化反应机理．结果表明，ＰｄＳＡＰＯ－５比ＳＡＰＯ－５和Ｐｄ／ＳＡＰＯ－５有更高的烯烃选择性，这是由于反应物凝胶中加入的钯对分子筛的酸性具有调节作用，加入不同形式的钯源，其调节作用有较大的差别，并使分子筛上甲醇及生成的二甲醇的脱附温度不同．此外，钯还充当了脱氢中心，可从二甲基已基氧离子中脱下一个氢原子，从而有利于乙烯的生成．ＮＭＲ结果表明，此类催化剂上的结炭存在多种形式．反应生成乙烯的甲氧基离子主要是二甲基乙基氧离子；甲醇在此类催化剂的部分钯粒子上脱氢生成ＣＨ２Ｏ．     

PdSAPO-5分子筛在甲醇转化反应中的催化性能及机理

用连续－脉微反应色谱评价了不同ＳＡＰＯ－５分子筛及一步法合成的ＰｄＳＡＰＯ－５催化剂对甲醇制烯烃反应的催化性能，用ＴＰＤ－ＭＳ及＾１３Ｃ ＣＰ ＭＡＳ ＮＭＲ研究了其催化反应机理。结果表明，ＰｄＳＡＰＯ－５比ＳＡＰＯ－５和Ｐｄ／ＳＡＰＯ－５有更高的烯烃选择性，这是由于反应物凝胶中加入的钯对分子筛的酸具有调节作用；加入不同形式的钯源，其调节作用有较大的差别，并使分子筛上甲醇及生成的二甲醚的脱附温度不     

中孔MCM—41分子筛在微孔沸石ZSM—5上附晶生长的研究

首次在微孔沸石ＺＳＭ５表面进行了ＭＣＭ４１分子筛的附晶生长，并首次提出中孔材料ＭＣＭ４１分子筛静电组配理论的新形式（ＸＳ＋Ｉ）；同时利用ＸＲＤ、ＴＥＭ、ＢＥＴ等测试手段表征了合成样品，并讨论了微孔沸石表面附晶生长中孔分子筛ＭＣＭ４１的合成化学，考察了Ｆ离子效应、ｐＨ值及表面活性剂ＣＴＡＢ（十六烷基三甲基溴化铵）的影响。     

苯乙烯在炭黑表面的阴离子接枝聚合研究

利用正丁基锂（ｎ－ＢｕＬｉ）与炭黑（ＣＢ）表面含氧基团反应制得了表面含－ＯＬｉ基团的反应型炭黑，以该炭黑与聚氧乙烯－聚氧丙烯－聚苯乙烯（ＰＥＯ－ＰＰＯ－ＰＳ）多嵌段聚合物组成的阴离子引发体系作活性中心，研究了苯乙烯在炭黑表面的阴离子接枝聚合。ＦＴ－ＩＲ，ＴＥＭ和ＤＳＣ分析表明在接枝炭黑表面存在苯乙烯的聚合物。接枝炭黑在甲苯中有良好的分散稳定性。     

聚丙烯酰胺与混合表面活性剂的相互作用

通过粘度和紫外吸收光谱的测定，研究了ＰＡＭ与Ｒ１２ＳＯ３Ｎａ－Ｒ１１ＣＯＯＮａ混合表面活性剂之间的相互作用，结果表明，ＰＡＭ可与混合表面活性剂形成复合物，从而使体系表现出典型聚电解质的粘度行为。可能的机理是，以疏水力形成的Ｒ１２ＳＯ３＾－—Ｒ１１ＣＯＯＨ（Ｎａ）预胶束或二聚体通过ＰＡＭ－Ｒ１１ＣＯＯＨ间的氢键力相结合。进而使大分子链上带有大量负电荷，静电斥力引起大分子链伸展，因而产生电粘效应。     

MCM－41中孔分子筛的合成及其性质

以十六烷基三甲基溴化铵（ＣＴＡＢ）作模板剂，研究了水热体系中中孔ＭＣＭ－４１分子筛的合成条件。在Ｈ_２Ｏ／Ｓｉ介于１２～１００，Ｓｉ／Ａｌ介于１０～∞，ＣＴＡＢ／Ｓｉ介于０．０８～０．２时，可以合成出ＭＣＭ－４１分子筛。在加入煤油等混合烃的合成体系中，可以合成出孔径大于４ｎｍ的ＭＣＭ－４１分子筛。用ＸＲＤ、ＳＥＭ、Ｎ_２吸附对合成样品加以表征，证明它们具有典型的中孔分子筛特性。探针反应证明它具有中强酸中心。     

阴离子X~-(F~-、Cl~-、Br~-)对中孔分子筛MCM-41合成与性质的影响

在凝胶体系ＮａＸ（Ｆ、Ｃｌ、Ｂｒ）Ｎａ２ＯＡｌ２Ｏ３ＳｉＯ２ＣＴＡＢ（十六烷基三甲基溴化铵）Ｈ２Ｏ中，研究了水热合成中孔ＭＣＭ４１的合成条件。实验证明，在３９８Ｋ下晶化８～１６ｄ，ＮａＸ／ＳｉＯ２介于０．０１～０．０５时，均可合成出ＭＣＭ４１分子筛；ＮａＦ的加入，可以加快ＭＣＭ４１分子筛的晶化速度；ＮａＢｒ的加入，对形成ＭＣＭ４１分子筛有阻碍作用。采用ＸＲＤ、ＳＥＭ、ＴＧＤＴＡ和Ｎ２吸附对合成样品加以表征，证明合成样品具有介孔分子筛特性。     

六方介孔硅酸盐的制备,表征及对苯酚羟化反应的催化作用

在室温下制备了Ｃｕ－ＨＭＳ（六方介孔硅酸盐）介孔含Ｃｕ杂原子分子筛，利用ＸＲＤ、ＩＲ和ＥＳＲ对其进行了表征，表明Ｃｕ原子已进入硅酸盐骨架．探讨了这种新型杂原子分子筛对苯酚羟化反应的催化作用，发现Ｃｕ－ＨＭＳ与Ｖ－ＨＭＳ，Ｔｉ－ＨＭＳ，ＴＳ－１，Ｃｕ－ＺＳＭ－５和Ｃｕ－Ｙ相比，具有较高的催化活性．研究了反应介质及ｐＨ值对苯酚羟化反应的影响，并给出了相应的反应机理     

Si、Zr取代磷酸铝沸石的合成与表征(英文)

利用水热法合成了 Ｓｉ、Ｚｒ取代型的ＡＰＯ－１１分子筛,井利用ＸＲＤ、ＳＥＭ、ＤＧ－ＤＴＡ等多种手段表征了其晶体结构、表面形貌、孔分布等特性。研究结果显示,ＡＰＯ－ｌｌ、ＳＡＰＯ－１１与ＺＡＰＯ－１１具有相同的晶体结构,不同的表面形貌－ＡＰＯ－１１与ＳＡＰＯ－１１为球形颗粒,而ＺＡＰＯ－１１为棒状晶体,推测这可能与ｐＨ对晶体生长的导向作用有关;三种分子筛除了具有为０．４５ ｎｍ的特征微孔孔径外,还形成了３．８ ｎｍ～３．９ ｎｍ的中孔;ＥＤＸ与孔分布结果显示,Ｚｒ主要以氧化物的形式沉积在分子筛的孔道内,而Ｓｉ部分进入了 ＡＰＯ－１１分子筛的骨架;三种分子筛的热稳定性良好,分解温度超过１０００℃。     

6－0－DEMETHYL－（19S）－DIHYDROETORPHINE， A NEW SYNTHETIC COMPOUND， ISOLATED FROM CRUDE DIHYDROETORPHINE AS A MINOR BY－PRODUCT

６－０－ＤＥＭＥＴＨＹＬ－（１９Ｓ）－ＤＩＨＹＤＲＯＥＴＯＲＰＨＩＮＥ，　Ａ　ＮＥＷ　ＳＹＮＴＨＥＴＩＣ　ＣＯＭＰＯＵＮＤ，　ＩＳＯＬＡＴＥＤ　ＦＲＯＭ　ＣＲＵＤＥ　ＤＩＨＹＤＲＯＥＴＯＲＰＨＩＮＥ　ＡＳ　Ａ　ＭＩＮＯＲ　ＢＹ－ＰＲＯＤＵＣＴ６－０－...     

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.