多金属氧酸盐纳米粉体室温固相合成、表征及催化性能

多金属氧酸盐纳米粉体室温固相合成、表征及催化性能;多金属氧酸盐;纳米粉体;固相合成;催化性能     

稀土元素11—钨锌合铝杂多配合物的合成,表征和催化性能

首次合成稀土元素１１－钨外合铝杂多配合物，用元素分析，红外光谱，紫外光谱，Ｘ射线光电子能谱和热分析等对合成产物进行了表征。其分子通式为；ＬｎＨ４「Ａｌ（Ｈ２Ｏ）ＺｎＷ１１Ｏ３９」．ｘＨ２Ｏ（Ｌｎ＝Ｌａ，Ｐｒ，Ｎｄ，Ｓｍ）。在此基础上，对其在合成己二酸二酯中的催化性能进行了研究。     

过氧钛杂多配合物位置异构体的合成、表征及催化性能

环氧化反应;催化活性;过氧钛杂多配合物位置异构体的合成、表征及催化性能     

M-HMS的合成、表征及在苯酚羟化反应中的催化性能

HMS-中孔分子筛;二酚;M-HMS的合成、表征及在苯酚羟化反应中的催化性能     

三铌和三过氧铌钨磷杂多配合物的合成、表征及催化性能

催化活性;三铌和三过氧铌钨磷杂多配合物的合成、表征及催化性能     

单铌和单过氧铌杂多配合物的合成、表征及催化性能

过氧铌钨磷杂多酸盐;催化活性;单铌和单过氧铌杂多配合物的合成、表征及催化性能     

氨基卟啉配合物的合成、表征和催化性能研究

合成了3种5－（4－乙二胺烷氧基）苯基－10，15，20－三苯基卟啉及其锰配合物，并用UV－Vis,IR,^1H NMR和LC－MCD表征了它们的结构。考察了这3种锰卟啉配合物对空气－乙苯体系直接羟基化的催化性能。结果表明，这种氨基卟啉配合物对空气氧化乙苯体系具有良好的催化作用，其催化活性比四苯基卟啉强3倍－4倍。     

钛取代的钨硅杂多配合物位置异构体的合成、表征及催化性能

钛取代的钨硅杂多配合物位置异构体的合成、表征及催化性能;钨钛杂多化合物;催化活性;环氧化反应     

铜(Ⅱ)、锰(Ⅱ)、镍(Ⅱ)高分子配合物的合成、表征与催化性质研究

合成出以乙二胺为核，马来酸酐为支化结构单元的马来酰胺树枝状高分子、高分子配体及其铜、锰、镍配合物，通过凝胶渗透色谱、红外光谱、紫外光谱、X-射线光电子能谱等对产物进行了结构表征，并就金属配合物对催化分解双氧水反应进行了研究。     

AlMn复合柱撑粘土负载CrCe催化剂用于氯苯催化降解性能初探

利用高温高压一步法合成系列Al Mn-复合柱化剂,该方法的步骤、物料消耗等较传统制备方法均大大减少,可大大降低生产成本及减少对环境的污染。通过离子交换合成系列Al Mn复合柱撑粘土(Al Mn-PILC)。改变Al/Mn摩尔比、老化温度、老化时间,可调控Al Mn-复合柱化剂的结构,从而影响Al Mn-PILC的结构性能(包括比表面积、孔体积、孔径、层间距等)。通过XRD,N2吸附,高分辨电镜及程序升温还原等实验对材料的结构及性能进行了表征。结果表明:经550℃焙烧4 h后,Al Mn-PILC的比表面积和孔体积可达174.2~246.7 m2·g-1和0.126~0.158 cm3·g-1,层间距可达1.85 nm。经柱撑改性合成的Al Mn-PILC,其负载Cr Ce催化剂对氯苯的催化降解性能远高于原土(Nammt)和单核Al-PILC的,尤其以Cr Ce(9∶1)/Al Mn-PILC的催化活性最佳,在250℃时可完全降解低浓度的氯苯,是一类性能优异的用于有机物催化降解的多孔材料。     

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.