反应条件对Zr—Mn—K催化剂合成甲醇,异丁醇的影响

用共沉淀法和超临界干燥法分别制备沉淀型Ｚｒ－Ｍｎ－Ｋ催化剂和超细Ｚｒ－Ｍｎ－Ｋ经剂，由合成气合成甲醇、异丁醇。考察了反应条件对两类催化剂合成甲醇、异丁醇的影响。超细催化剂生成异丁醇活性明显高于沉淀催化剂。在４００℃、５０００ｈ＾－１、１０．０ＭＰａ的反应条件下，超细催化剂异丁醇的含量可达１７．３１％，时空产率为１８．２ｍｌ／ｈ．Ｌｃａｔ．，１６ＭＰａ时异丁醇时空产率达３３．９２ｍｌ／ｈ．Ｌｃａｔ。     

Zr—Mn—K催化超临界相合成甲醇与异丁醇的研究

用共沉淀法和超临界流体干燥法,分别制备了Ｚｒ－Ｍｎ－Ｋ沉淀型催化剂和超细催化剂。以正十一－十三烷的混合物为超临界介质,在反应温度３６０－４１０℃,合成气压力为７．５ＭＰａ,ＧＨＳＶ１７００ｈ＾－１及介质压力２．０８ＭＰａ的实验条件下,分别考虑了超细催化剂和沉淀催化剂的气相和超临界相催化合成气制甲醇,异丁醇的性能。     

稀土助剂对Zr－Mn－K催化剂上甲醇、异丁醇合成的影响

在Ｚｒ－Ｍｎ－Ｋ催化剂中添加稀土氧化物助剂Ｐｒ６Ｏ_（１１）、Ｓｍ_２Ｏ_３可以显著提高合成气合成甲醇、异丁醇的活性，特别是异丁醇的时空产率在４００℃、１０ＭＰａ、５０００~（－１）的反应条件下，由原来的５．９分别增加到１１．５、９．８ｍｌ／ｈ·ｌｃａｔ．。催化剂的ＸＲＤ、ＬＲＳ、ＴＰＲ、ＴＥＭ图和比表面测定结果一致表明，稀土元素可使催化剂晶粒细化、高度分散，稳定了四方相。ＸＰＳ结果表明：ＲＥＯ的加入使表面Ｍｎ富集，且催化剂表面Ｍｎ和Ｋ的比例影响其合成甲醇、异丁醇的活性与选择性。     

稀土助剂对Zr—Mn—K催化剂上甲醇,异丁醇合成的影响

在Ｚｒ－Ｍｎ－Ｋ催化剂中添加稀土氧化物助剂Ｐｒ６Ｏ１１，Ｓｍ２Ｏ３可以显著提高合成气合成甲醇，异丁醇的活性，特别是异丁醇的时空产率在４００℃，１０ＭＰａ，５０００＾－１的反应条件下，由原来的５．９分别增加到１１．５，９．８ｍｌ／ｈ．ｌｃａｔ。     

Zr-Mn-K催化剂超临界相合成甲醇与异丁醇的研究

用共沉淀法和超临界流体干燥法,分别制备了Ｚｒ－Ｍｎ－Ｋ沉淀型催化剂和超细催化剂．以正十一～十三烷的混合物为超临界介质,在反应温度３６０～４１０℃、合成气压力７．５ＭＰａ、ＧＨＳＶ１７００ｈ－１及介质压力２．０８ＭＰａ的实验条件下,分别考察了超细催化剂和沉淀催化剂的气相和超临界相催化合成气制甲醇、异丁醇的性能．气相和超临界相反应的研究均表明,超细催化剂催化合成异丁醇的活性高于沉淀催化剂;在超临界条件下反应,超细催化剂上产物的异丁醇含量较高（为２３％～３２％）,甲醇含量为２２％～３３％,其它醇均在１０％左右．气相与超临界相反应结果的对比显示,超临界流体促进产物的脱附与传递,提高了ＣＯ的转化率．但超临界流体对甲烷的萃取作用强于对醇的萃取,醇选择性低于气相反应．在超临界条件下合成甲醇、异丁醇仍遵循异丁醇形成的链增长机理,超临界流体改变了链增长各步骤的相对速度,致使超临界相反应的产物分布不同于气相反应的产物分布．     

钌催化剂存在下的氨湿法氧化反应条件与N2选择性

在完全除去铵离子的湿法氧化反应中，一种钌催化剂能够将文献报道的反应条件从５４３Ｋ，７．０ＭＰａ缓和为４５３Ｋ，３．０ＭＰａ但是，在相对温和的反应条件下，Ｎ２选择性不够理想，并受到操作条件如ｐＨ，反应温度，空填充压力及催化剂用量的影响。     

合成甲醇,异丁醇锆系催化剂的晶相结构

用ＬＲＳ和ＸＲＤ相结合方法对Ｚｒ－Ｋ和Ｚｒ－Ｍｎ－Ｋ催化剂进行了。考察共沉淀法制备的Ｚｒ－Ｋ、Ｚｒ－Ｍｎ－Ｋ催化剂焙烧温度和Ｋ２Ｏ、ＭｎＯ２含量对其晶相结合的影响。在Ｚｒ－Ｋ催化剂中，ＺｒＯ２以单斜和四方混合晶型存在，在Ｚｒ－Ｍｎ－Ｋ催化剂中，当ＭｎＯ２含量在１７－３０％时，催化剂中仅有高度分散的四方晶型晶型ＺｒＯ２它是合成甲醇、异丁醇的活性相。     

二氧化碳与正丁醇,异丁醇二元体系高压相平衡研究

使用自行设计的两相交替循环式高压实验装置，测定了ＣＯ２－正丁醇和ＣＯ２－异丁醇两个二元体系的相平衡数据，温度范围分别为３１３．Ｋ－３３３．２Ｋ和２９８。２Ｋ－３２８．２Ｋ。压力范围是０．６ＭＰａ左右到各体系的临界点附近。测定结果用ＰＲＳＶⅡ方程结合两参数混合规则进行了关联，在压力大于２ＭＰａ的区域里，取得了较满意的结果。     

COS对FT合成催化性能的影响

在５２４Ｋ、２．３１ＭＰａ和１８４５ｈ＾－１条件下，考察了合成气（Ｈ２／ＣＯ＝２．１）中ＣＯＳ浓度分别为５１．４、１２８．８、１６２．７和２４５．６ｐｐｍ对Ｆｅ－Ｃｕ－Ｋ工业催化剂ＦＴ合成催化性能的影响。实验表明，催化剂预先中毒比在线中毒速度快。大颗粒催化剂的抗硫能力比小颗粒催化剂强。催化剂ＦＴ合成失活速率与ＣＯＳ浓度有关，即高浓度条件下，催化剂的失活速率快。当温度为５２４Ｋ时，催化剂的失活速率最     

超临界相CO加氢合成甲醇,异丁醇的研究

以正十一～十三烷的混合物为超临界介质,在反应温度３６０～４１０℃、合成气压力７５ＭＰａ、进气空速１７００ｈ－１、介质压力１７８ＭＰａ、总压９３ＭＰａ的实验条件下,研究了固定床反应器中Ｚｎ－Ｃｒ、Ｃｕ－Ｚｎ－Ｃｒ催化剂在超临界相和气相条件下合成甲醇、异丁醇的性能。结果表明,超临界相反应的ＣＯ转化率高于气相反应。在超临界条件下反应,醇类选择性随着温度升高下降较慢,而气相反应醇类选择性随着温度升高下降较快。气相反应产物以甲醇、异丁醇为主,含少量乙醇和正丙醇,超临界相反应的产物分布与气相反应的明显不同,甲醇含量减少,乙醇、正丙醇和异丁醇都有不同程度增加。超临界流体的存在对合成醇链增长有影响,在不同催化剂上的产物分布有较大差异     

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.