过氧杂多阴离子柱撑水滑石类层状化合物的合成与表征

以硝酸根型水滑石作交换前驱体，通过离子交换法合成了过渡金属离子一、三钛取代的Ｋｅｇｇｉｎ结构过氧钨硅杂多阴离子柱撑水滑石Ｚｎ２Ａｌ（ＯＨ）６－［ＳｉＷ１１（ＴｉＯ２）Ｏ３９］及Ｚｎ２Ａｌ（ＯＨ）６－［ＳｉＷ９（ＴｉＯ２）３Ｏ３７］，用元素分析、ＸＲＤ、ＩＲ、ＸＰＳ、化学分析等手段对产物的组成和结构进行了表征。结果表明，过氧杂多阴离子进入水滑石层间，使水滑石的层间距从０．９２ｎｍ增加到１．４７ｎｍ。     

钨硅系列三元杂多阴离柱撑阴离子粘土的合成及表征

采用离子交换法将过渡金属离了三元取代钨杂多阴离子引入Ｚｎ２Ａｌ型阴离子粘土层内，得到柱撑水滑石Ｚｎ２Ａｌ（ＯＨ）６－ＳｉＷ９Ｚ３Ｏ４０（Ｚ＝Ｔｉ＾４＋，Ｍｏ＾６＋）及Ｚｎ２Ａｌ（ＯＨ）６－ＳｉＷ９Ｆｅ３（Ｈ２Ｏ２）３Ｏ３７。ＺＲＤ及ＩＲ表明，杂多阴离子引入水滑石层间后，水滑石层内高度为１．０ｎｍ。     

Keggin结构磷钨钒杂多阴离子柱撑水滑石的合成、表征与热稳定性研究

采用水浴液中阴离子直接交换法合成了具有不同钒含量的Ｋｅｇｇｉｎ结构磷钨钒杂多阴离子ＰＷ（１２－ｎ）ＶｎＯ（４０）（ｎ＝１—５）柱撑水滑石，用元素分析、ＸＲＤ和ＩＲ对柱撑产物的组成和结构进行了表征．ＸＲＤ结果给出柱撑产物的底面间距达１．４７Ｍ．ＤＴＡ结果表明柱撑产物的热稳定性高于水滑石前驱体，且与杂多阴离子中Ｖ含量相关．由不同温度下焙烧样品的ＸＲＤ和ＩＲ研究可知，柱撑产物的热分解过程为：＜２５０℃时脱除物理吸附水和层间水；２５０～４００℃范围内脱羟基（同时伴随着层间Ｋｅｇｇｉｎ离子结构的破坏）；４００℃以上生成ＷＯ３和Ｍｇ２Ｖ２Ｏ７，后者在７５０℃以上分解为ＭｇＯ和Ｖ２Ｏ５．     

新型层柱材料ZnAl─CuW11In的合成、表征及催化活性

本文用水热离子交换法首次将中心原子为铜的钨系取代型杂多阴离子［ＣｕＷ１１Ｏ３９Ｉｎ（Ｈ２Ｏ）］７－嵌入ＺｎＡｌ型阴离子粘土层间，通过ＸＲＤ、ＩＲ及ＥＳＲ等对柱撑产物进行了表征。ＸＲＤ研究表明柱撑产物的底面间距为１．７５ｎｍ，通道高度达１．２８ｎｍ。ＥＳＲ结果显示杂多阴离子进入粘土层间后ＣｕＯ４四面体中Ｃｕ－Ｏ键的共价性减弱。催化实验则表明柱撑产物对邻苯二甲酸二辛酯（ＤＯＰ）的合成反应有较高的催化活性     

新型层柱材料ZnAl─CuW11In的合成、表征及催化活性

本文用水热离子交换法首次将中心原子为铜的钨系取代型杂多阴离子［ＣｕＷ１１Ｏ３９Ｉｎ（Ｈ２Ｏ）］＾７－嵌入ＺｎＡｌ型阴离子粘土层间，通过ＸＲＤ、ＩＲ及ＥＳＲ等对柱撑产物进行了表征。ＸＲＤ研究表明柱撑产物的底面间距为１．７５ｎｍ，通道高度达１．２８ｎｍ。ＥＳＲ结果显示杂多阴离子进入粘土层间后ＣｕＯ４四面体中Ｃｕ－Ｏ键的共价性减弱。催化实验表明柱撑产物对邻苯二甲酸二辛酯（ＤＯＰ）的合成反应有较好的催化活     

类水滑石及其杂多阴离子柱撑物的合成与表面酸性研究

合成了一些类水滑石和过渡金属取代型杂多酸盐，并由此制备了相应杂多阴离子柱撑水滑石层柱材料。用ＸＲＤ，ＩＲ和元素分析等手段对合成产物进行组成和结构表征，用ＮＨ３－ＴＰＤ，Ｐｙ－ＩＲ研究了合成产物的表面酸性和酸类型，并在异丙醇反应中考察了合成物的酸碱催化行为，结果表明，水滑石和柱撑水滑石均同时存在酸碱中心，且酸碱相对强度与柱阴离子类型密切相关。杂多阴离子进入水滑石层，同时改变了水滑石和杂多酸盐的酸强度     

P—W系杂多阴离子柱水滑石的制备及表征

本文采用微波法，首次制了第四周期系过滤金属取代三元杂多阴离子（ＰＺＷ１１）柱水滑石。经ＸＲＤ、ＤＴＡ、ＩＲ、ＵＶ－ＤＲＳ和ＥＳＲ表征。结果表明插入层间的柱高约为１．０ｎｍ，进入水滑石层间的杂多阴离子与其盐的ＩＲ振动类型和振动频率很相近，并且在水滑石层间ＰＷ１２基团不能稳定存在，可能已部分发生降解，而ＰＺＷ１１则能稳定的存在于水滑石层间。ＵＶ结果表明，进入水滑石层间的杂多阴离子的桥氧与钨（Ｏｂ／Ｏｃ     

杂多阴离子柱撑水滑石类层柱材料中层柱相互作用研究

合成了具有不同组成的类水滑石层状化合物和杂多酸，据此制备了一系列杂多阴离子柱撑水滑石，用ＩＲ光谱、ＤＴＡ等方法研究了此类层柱材料中层与柱的相互作用，发现类水滑石层状化合物中的Ｍ＾３＋离子的种类和具有Ｋｅｇｇｉｎ结构的杂多阴离子的组成元素，无论处于四面体中、还是位于八面体中，对层柱的相互作用皆有明显影响，此外，这种相互作用还导致杂多阴离子中四面体和八面体对称性及相关性质的改变。     

杂多阴离子柱撑水滑石层柱相互作用(Ⅰ)

杂多阴离子柱撑水滑石层柱相互作用（Ⅰ）李兴林＊佘益民郭军蒋大振（中国科学院长春应用化学研究所长春１３００２２）（吉林大学化学系长春）关键词杂多阴离子，柱撑水滑石，ＸＰＳ，ＩＲ，ＸＲＤ１９９６－０６－１８收稿，１９９６－１０－１２修回国家自然科学基金资...     

新型层柱微孔材料──FeW_（11）NiO_（39）柱撑ZnAl阴离子粘土的合成、表征及催化性能

采用水热合成与离子交换方法，将中心原子为过渡金属（Ｆｅ）的钨系过渡金属取代型杂多阴离子ＦｅＷ_（１１）ＮｉＯ_（３９）（Ｈ_２Ｏ）￣（７－）（缩写为ＦｅＷ_（１１）Ｎｉ）嵌入ＺｎＡｌ型阴离子层状结构粘土间，获得了大层间距、通道高度达１．３２ｎｍ的新型层柱微孔化合物。通过ＸＲＤ、ＩＲ及ＥＳＲ等手段进行了表征。以ＺｎＡｌ－Ｆｅｗ_（１１）Ｎｉ为催化剂合成邻苯二甲酸二辛酯（ＤＯＰ），选择性大于９９％，转化率由嵌入前的１２％提高到近５０％，催化活性明显提高。     

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.