一些无机盐对甲烷的液相选择催化氧化

考察了无机盐Ｃｒ２（ＳＯ４）３，ＣｄＳＯ４，ＦｅＳＯ４，ＶＯＳＯ４，Ｃｅ（ＳＯ４）２，ＭｎＳＯ４，ＳｎＣｌ４和ＨｇＳＯ４在浓硫酸介质中对甲烷的催化活性，发现ＭｎＳＯ４，ＳｎＣｌ４和ＨｇＳＯ４对甲烷氧化有活性，在此基础上考察了ＨｇＳＯ４体系中气液体积比，温度，浓度，反应时间以及硫酸浓度地反应活性的影响，认为反应按亲电取代反应机理进行。     

硅胶负载钒磷氧化物催化2 ,6-二氯甲苯氨氧化反应(英)

对硅胶负载钒磷氧化物（ＶＰＯ） 催化剂（ ｎ（Ｖ）／ ｎ（Ｐ） ＝ １） 催化２ ,６二氯甲苯（ＤＣＴ） 氨氧化反应进行了研究． 考察了反应温度、空气／ＤＣＴ 比和氨／ＤＣＴ 比等因素对反应的影响． 反应温度对氨氧化反应影响较大,空气／ＤＣＴ比和氨／ＤＣＴ 比对反应的影响不很大． 最佳反应条件为： Ｔ＝ ６７３ Ｋ, ｎ（ａｉｒ）／ｎ（ＤＣＴ） ＝ ３０ , ｎ（ＮＨ３）／ｎ（ＤＣＴ）＝ ６ ． 在此条件下,ＤＣＴ转化率为９０ ％ , 产率为５７ ％ ． 与使用（ＮＨ４）２［（ＶＯ）３（Ｐ２Ｏ７）２］ 催化剂的文献报道值相比,反应温度降低４０ Ｋ, 产率提高３４ ％ ．ＸＲＤ分析结果表明, ＶＰＯ／ＳｉＯ２ 催化剂中的活性组分以均匀分散的无定形状态存在,而未负载的ＶＰＯ催化剂中存在αＶＯＰＯ４ 和βＶＯＰＯ４ 晶相．     

LaCaMnO3催化剂活性相的结构和形成机理的研究

利用ＴＧ，ＤＴＡ，ＸＲＤ和ＸＰＳ方法研究了Ｌａ０．２Ｃａ０．８ＭｎＯ３催化剂的结构和形成机理。样品用Ｌａ，Ｃａ，Ｍｎ混合硝酸盐制备。随着焙烧温度的升高发生的一系列的固相反应，发现氨氧化催化剂催化活性与生成的ＣａＭｎＯ３含量成正比。在９００℃制备的含有ＣａＭｎＯ３，Ｌａ０．５７５Ｃａ０．４２５ＭｎＯ３，Ｍｎ２Ｏ３和Ｌａ２Ｏ３的混合物是氨氧化最佳催化剂，活性相是ＣａＭｎＯ３，并具有大量的氧空穴。     

载Sn离子交换树脂酸催化性能的研究

本文将ＳｎＣｌ４与Ｄ００１离子交换树脂上的磺酸基团发生络合反应，形成Ｈ０≤－１１．３５，且不会被阳离子交换而失活的的酸中心，从而使Ｄ００１．Ｓｎ树脂的酸催化活性明显提高。以乙酸和正丁醇的液相酯化反应为模型，Ｄ００１．Ｓｎ催化剂能使该反应在试验条件下的表观活化能从１１１．０ｋＪ／ｍｏｌ降低到３９．０ｋＪ／ｍｏｌ。在连续分水的最佳反应条件下，乙酸丁酯５ｈ产率可达９８．７％，优于等当量Ｈ２ＳＯ４的催化活     

水蒸汽对负载型催化剂丙烷脱氢性能的影响：Ⅰ.反应性能的研究

研究了ＭｇＡｌ２Ｏ４，ＺｎＡｌ２Ｏ４负载的Ｐｔ－Ｓｎ催化剂在氮气及水蒸汽中的丙烷脱氢性能。考察了还原温度，反应温度，催化剂载量对Ｐｔ－ＳＳｎ／ＭｇＡｌ２Ｏ４催化剂丙烷脱氢性能的影响。     

纳米尖晶石型Co2MnO4的形成过程及其F-T反应性能

用溶胶凝胶法制备了尖晶石型Ｃｏ２ＭｎＯ４超细粒子，用ＤＴＡＴＧ，ＸＲＤ，ＴＥＭ，ＦＴＩＲ等手段研究了Ｃｏ２ＭｎＯ４超细粒子的形成过程，进而用反应评价结合ＸＲＤ，ＸＰＳ，ＢＥＴ比表面积测试研究了Ｃｏ２ＭｎＯ４催化剂的比表面积和表面结构与其ＦＴ反应性能间的关系．结果表明，Ｃｏ２ＭｎＯ４超细粒子可以在较低温度（２５０～３５０℃）下形成，并具有粒度小，分布均匀等特点．用该法制备的超细粒子Ｃｏ２ＭｎＯ４，其催化活性明显优于相同组成的大颗粒催化剂．     

流动注射—原子吸收法测定药物制剂中的维生素B6

１引言在弱酸性介质中，新生态ＭｎＯ２与维生素Ｂ６（ＶＢ６）发生反应，通过ＦＩＡ－ＡＡＳ测定反应产物Ｍｎ２＋，建立了测定ＶＢ６含量的新方法。方法具有简便、快速、重现性好等优点，用于实际样品的测定，结果与药典法一致。２实验部分２．１仪器与试剂ＧＦＵ－２０２型原子吸收分光光度计；ＩＦＩＳ－Ｂ型智能流动注射进样器；Ｍｎ２＋标准溶液（１ｇ／Ｌ）；ＶＢ６标准溶液（１ｇ／Ｌ）；新制ＭｎＯ２＋：在０．２５％ＫＭｎＯ４溶液中逐滴加入０．５％ＭｎＳＯ４（其中含硫酸１ｍｏｌ／Ｌ）至红色完全消失。新制得的ＭｎＯ２保存在…     

CuZSM-5分子筛上苯酚羟化制苯二酚

在Ｎａ２Ｏ－ＳｉＯ２－ＣｕＯ－Ｈ２Ｏ体系中以１５％ＴＰＡＢｒ－８５％ＨＭＤＡ为模板剂合成了ＣｕＺＳＭ－５分子筛，并用ＸＲＤ，ＩＲ及ＳＥＭ等方法进行了表征，考察了ＣｕＺＳＭ－５分子筛催化苯酚与过氧化氢的羟化活性，研究了催化剂用量、反应温度、反应时间及ｎ（ＰｈＯＨ）／ｎ（Ｈ２Ｏ２）等对羟化活性的影响．     

乙二醇甲醚—水溶液作介质水热法合成四方相ZrO3.3%Y2O3纳米晶

利用新沉淀的Ｚｒ（ＯＨ）４．３％Ｙ（ＯＨ）３．ｎＨ２Ｏ作前驱体，以乙二醇甲醚－水溶液作反应介质，水热法合成了四方相ＺｒＯ２．３％Ｙ２Ｏ３纳米晶，考察了反应介质，ＰＨ值，反应温度及Ｃｌ＾１、ＮＯ＾３－和ＳＯ＾２－４对产物的影响。前驱体对产物物相有重要影响。     

非均相电解Mn^2＋的电极过程动力学研究

选择Ｐｂ－Ｓｂ－Ａｓ合金为研究电极，通过阳极极化曲线确定了非均相电解氧化Ｍｎ６２＋电极过程机理，即为在阳极上存在液相和固相两个反应；并确定了４０％Ｈ２ＳＯ４介质中Ｍｎ／Ｍｎ体系的条件电极电势为０．８８６Ｖ。采用旋转圆盘电极研究得到在非均相电解ＭｎＳＯ４过程中电极过程控制步骤为电荷传递－浓度极化混合控制步骤，并确定了电极反应的动力学参数。     

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.