低碳醇合成中异丁醇形成机理及提高其收率的途径

在压力１０ＭＰａ，温度３６０～４２０℃，尾气空速３０００～７０００ｈ￣（－１）的反应条件下，采用分别富集甲醇、乙醇、正丙醇和异丙醇的方法，研究Ｚｎ－Ｃｒ－Ｋ氧化物催化剂上异丁醇的形成机理，并探讨利用甲醇循环提高其收率的可能性。结果表明，低碳醇的形成是以碳链增长形式进行的，ＣＯＨ→ＣＣＯｏＨ慢的α－加成反应是链增长的起始步骤，也是低碳醇合成反应的控制步骤，β－加成是生成低碳醇的特征反应，ＣＯＨ→ＣＣＯＨ→ＣＣＣＯＨ→ＣＣ（ＣＨ＿３）ＣＯＨ是异丁醇的形成机理。甲醇富集对提高异丁醇收率有明显的促进作用，采用甲醇循环技术提高异丁醇收率是可行的。     

真空冷冻干燥法制备CuO—ZnO—Al2O3合成甲醇催化剂

研究了用真空冷冻干燥法制备ＣｕＯ－ＺｎＯ－Ａｌ２Ｏ３催化剂，提出用叔丁醇代替水作介质的新方法，采用该方法可以使干燥速度显著加快。考察了反应温度，压力，空速及催化剂组成对ＣＯ２＋Ｈ２催化合成甲醇的影响。     

MoCl_5与n－C_7H_（15）COOH的取代反应及其产物对丁二烯聚合活性

研究了ＭｏＣｌ５与ｎ－Ｃ７Ｈ１５ＣＯＯＨ间的取代反应条件，如反应温度和时间等，对取代反应产物ＭｏＣｌ５－ｍ（ｎ－Ｃ７Ｈ１５ＣＯＯ）ｍ的影响，讨论了产物的紫外可见光谱，测定了由取代产物组成的铝催化剂对丁二烯聚合反应的活性，结果表明，随着ＭｏＣｌ５中氯的取代量（ｍ＝２～４）的增加聚合活性迅速降低。     

担载型钌催化剂吸附CO性能的原位红外研究

用原位红外研究了ＣＯ的吸附与脱附，ＣＯ／Ｈ２的共吸附及反应，考察了焙烧温度对Ｒｕ／Ａｌ２Ｏ３及Ｒｕ／ＳｉＯ２催化剂的影响，结果表明，经不同温度焙烧的催化剂样品，其吸附性能有很大差别。随着焙烧温度的升高，金属－载体相互作用增强，导致ＣＯ吸附量减少。Ｒｕ／Ａｌ２Ｏ３吸附的ＣＯ较稳定，而Ｒｕ／ＳｉＯ２吸附的ＣＯ在高温易脱附。各不同ＣＯ吸会态间、多重态更易发生反应。在未焙烧的Ｒｕ／ＳｉＯ２低ＣＯ／Ｈ２反应     

苯磺酸甲酯醇解反应的动力学研究

苯磺酸甲酯醇解反应的动力学研究赖国华，胡科诚，金松寿（杭州大学化学系杭州３１００２８）关键词动力学，苯磺酸甲酯醇解，补偿效应本文研究了苯磺酸甲酯在ＣＨ＿３ＯＨ，Ｃ＿２Ｈ＿５ＯＨ，ｎ－Ｃ＿３Ｈ＿７ＯＨ和ｎ－Ｃ－４Ｈ＿９ＯＨ中的醇解反应速率随温度的变化情...     

Ni／Al2O3催化剂上CH4／CO2重整的脉冲反应研究

报道了用脉冲反应研究Ｎｉ／Ａｌ２Ｏ３催化剂上ＣＨ４／ＣＯ２重整反应的结果。脉冲反应显示，在还原的Ｎｉ／Ａｌ２Ｏ３催化剂上，ＣＨ４在６７３Ｋ就开始发生分解，并有Ｃ２Ｈ６、Ｃ２Ｈ４生成，１０２３Ｋ下，ＣＨ４几乎完全分解，单纯的ＣＯ２则很难在还原的催化剂上发生反应，在９７３Ｋ以上的高温下才会有少量Ｃ胜成ＣＯ．ＣＨＣＯ２的脉冲反应表明，当ＣＨ４在较低温度下开始分解时，ＣＯ２也会发生分解，并生成ＣＯ。脉冲反     

水溶性铑—膦配合物催化长链烯烃氢甲酰化反应研究—反应条件的影响

本文研究了两相催化体系中，在ＣＴＡＢ（Ｃ１６Ｈ３３ＮＭｅ３Ｂｒ）存在下，水溶性铑－膦配合物ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）２对１－己烯氢甲酰化反应的催化性能，详细考察了反应温度、压力、膦／铑比等对催化活性的影响。结果表明，在１．０ＭＰａ恒压下，反应温度１００℃，膦／铑摩尔比为１６，Ｈ２：ＣＯ＝１：１的条件下，１－己烯氢甲酰化的转化频率（ＴＯＦ）可达到３９．８ｍｉｎ＾－１。在此反应条件下，有机相和水相     

铁—芳烃络合物引发氧化环己烯阳离子光聚合反应动力学…

以环戊二烯异丙苯铁六氟磷酸盐为引发剂，用示差扫描量热法研究了氧化环己烯（ＣＨＯ）阳离子聚合反应动力学。实验结果表明，温度对ＣＨＯ聚合反应影响很大。ＣＨＯ在一系列温度下等温聚合时，放热量和转化率均在４０℃左右最高，而聚合反应速率则随着温度的升高而降低。ＣＨＯ聚合反应属一级反应，化能为－９．８７ｋＪ／ｍｏｌ，并对聚合反应历程进行了理论推导，其结果与实验结果相符合。     

铑基CO加氢制乙醇催化剂的FTIR研究

用ＦＴＩＲ的Ｒｈ／ＣｅＯ２／ＳｉＯ２系列ＣＯ加氢制乙醇催经剂进行了研究，在Ｈ２流中升温处理时，吸附ＣＯ的脱附温度低于Ｎ２气流中ＣＯ的脱附温度，ＣｅＯ２的加入进一步降低了Ｎ２和Ｈ２气流中ＣＯ的脱附温度，在Ｈ２气流中升温处理时，相邻双羰基峰的低波数峰迅速消失，而高波数峰变得不对称，ＦＴＩＲ结果表明，在ＣＯ加氢反应中，催化剂表面上生成了Ｒｈ（Ｈ）ＣＯ物种，反应的速度决定步骤很可能是这一物种的进一步反应，     

浆态相低温甲醇合成用的CuCr／CH3ONa催化体系的反应性能

在液相介质为二甲苯，甲醇或液体石蜡，温度１００～１４０℃，压力３．５～４．７ＭＰａ条件下，使用Ｈ２／ＣＯ＝２的合成气，在１Ｌ搅拌釜内考察了自制的ＣｕＣｒ／ＣＨ３ＯＮａ催化体系的浆态相低温甲醇合成的反应性能，结果表明液相介质以二甲苯为佳，ＣＯ转化率随压力而升高，温度以１２０℃为宜。４４ｈ的连续运转表明以ＣＯ转化率为代表的催化体系的反应性能基本稳定。     

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.