高分散费-托合成铁/活性炭催化剂的研究Ⅲ.碳化性质

使用原位穆斯堡尔谱考察了具有不同担载量的Fe/AC以及Fe-K/AC和Fe-Mn/AC催化剂在300℃合成气(H_2/CO=2)中的碳化行为。发现在活性炭载体上铁的担载量(或分散度)制约着碳化时生成的碳化铁的种类。铁的粒径很小(～30A)时生成ε’-Fe_(2·2)C碳化铁,铁的粒径在70A左右可生成ε-Fe_2C碳化铁,而大粒子铁(>200A)和体相铁则生成x-Fe_5C_2碳化铁,Fe-K/AC和Fe-Mn/AC催化剂在碳化时生成的碳化铁种类仍受铁的粒径制约,助剂K和Mn不影响生成的碳化铁的种类,但Mn可延缓铁的碳化。     

铁羰基络合物制备的一氧化碳加氢催化剂的研究

本文采用Ｆｅ＿３（ＣＯ）＿（１２）制备担载型络合物催化剂。采用程序升温反应技术考察了这类催化剂（ＣＯ＋Ｈ＿２）的反应性能，井使用紫外漫反射光谱和穆斯堡尔谱对催化剂进行了表征。经２５０℃和１５０℃还原的Ｆｅ／γ－Ａｌ＿２Ｏ＿３催化剂不仅活性远远高于４５０℃还原的Ｆｅ／γ－Ａｌ＿２Ｏ＿３，而且前者在反应过程中有乙烯和乙烷生成，后者则只有甲烷生成。经２５０℃还原的Ｆｅ／分子筛催化剂的活性高于４５０℃还原的Ｆｅ／分子筛催化剂，而且前者在反应过程中有乙烯、乙烷和丙烯生成，后者则只有甲烷生成。紫外漫反射谱和穆斯堡尔谱结果表明：较温和条件下活化的催化剂上有金属于属键骨架的存在。     

镧改性铁催化剂的研究Ⅱ.镧改性铁催化剂的碳化性能

用穆斯堡尔谱和Ｃａｈｎ微量天平技术研究了Ｆｅ２Ｏ３／γ－Ａｌ２Ｏ３，Ｆｅ２Ｏ３－Ｌａ２Ｏ３／γ－Ａｌ２Ｏ３和Ｆｅ２Ｏ３／Ｌａ２Ｏ３／γ－Ａｌ２Ｏ３催化剂的碳化性能。结果表明：铁碳化物的生成与催化剂活性组分同载体的相互作用有关。Ｌａ２Ｏ３改性后的Ｆｅ２Ｏ３／Ｌａ２Ｏ３／γ－Ａｌ２Ｏ３催化剂，由于活性组分与载体之间存在强相互作用，在Ｆ－Ｔ反应过程中没有检测到铁碳化物相。同时，Ｌａ２Ｏ３的添加提高了催化     

氧化锆负载氧化铁催化剂上CO加氢反应的研究钾,锰,镧,铈的助剂作用

应用Ｘ－射线衍射，程序升温还遥，穆斯堡尔谱以及ＣＯ＋Ｈ２催化反应性能测试等手术研究了Ｋ，Ｍｎ，Ｌａ，Ｃｅ四种助剂对Ｆｅ２Ｏ３／ＺｒＯ２催化剂结构，还原行为以及ＣＬ＋Ｈ２反应催化性能的影响。     

Fe_2O_3／ZrO_2催化剂上一氧化碳加氢反应制低碳烯烃──I．催化剂反应性能及反应过程中铁物相的变化

用浸渍法制得一系列不同铁负载量的Ｆｅ２Ｏ３／ＺｒＯ２催化剂，应用催化反应评价结合穆斯堡尔谱对催化剂的ＣＯ加氢反应性能、催化剂活性相结构及催化剂铁物种在合成气反应过程中的物相变化进行了研究．结果表明，铁负载量的大小对于Ｆｅ２Ｏ３／ＺｒＯ２催化剂的Ｆ－Ｔ反应催化性能有很大影响，铁负载量适当时，Ｆｅ２Ｏ３／ＺｒＯ２催化剂铁锆间适当的强相互作用使得催化剂在保持较高催化活性的同时高选择性地生成低碳烯烃，产物分布偏离Ｓｃｈｕｌｚ－Ｆｌｏｒｙ分布规律．     

浆态床FT合成中铁催化剂的穆斯堡尔谱

浆态床ＦＴ合成中铁催化剂的穆斯堡尔谱赵玉龙，李哲（中国科学院山西煤炭化学研究所煤转化国家重点实验室，太原）（中国科学院地质研究所，北京）关键词穆斯堡尔谱，铁催化剂，浆态床ＦＴ合成ＦＴ合成铁系催化剂的穆斯堡尔谱的研究工作已经发表很多，但是浆态操作条件下...     

高分散费-托合成铁/活性炭催化剂的研究——Ⅰ.铁/活性炭催化剂的恒温还原及其穆斯堡尔谱

使用原位穆斯堡尔谱研究了非担载铁氧化物和不同担载量的铁/活性炭催化剂在不同温度下的还原,详细分析了活性炭载体上高分散超顺磁铁物类的穆斯堡尔谱。还原前铁/活性炭催化剂中的铁物类为结构松散的α-Fe_2O_3和没有充分脱水的氧化铁,铁的担载量不很小时可经Fe_3O_4还原到金属态,但活性炭载体可稳定Fe~(3+)使之难以还原,在500℃氢气中大部分铁才还原为金属。铁的担载量很小时,其还原以Fe~(2+)为中间产物,0.2%Fe/AC氢气化剂在500℃氢气还原18小时生成磁分裂金属铁和超顺磁金属铁(δ=0.37mm/s,△=0,H=0),其正的同质异能移表示了铁-活性炭间的电荷转移。     

碳氧定向反应Fe／C系催化剂中助剂的作用

本文采用微反－色谱，穆斯堡尔谱及ＸＰＳ等分析手段，研究了碳氧定向反应生成ＣＯ的Ｆｅ／Ｃ系催化剂中助剂Ｋ，Ｃｒ的作用。结果表明，助剂能大大提高定向氧化反应活性，并能稳定主活性组分的价态和提高其分散度。复合催化剂Ｆｅ－Ｋ－Ｃｒ／Ｃ无论在催化活性，稳定性及抗烧结性能方面都优于单组分催化剂。     

铁基高温变换催化剂制备的穆斯堡尔谱研究Ⅰ.铁氧化物前驱态的相变过程

用穆斯堡尔谱及ＸＲＤ技术对不同铁氧化物前驱态的相变过程进行了，ＦｅＣＯ３沉淀在空气中老化时被氧化分解生成ＦｅＯ（ＯＨ），经干燥、煅烧后合部转化为ａ－Ｆｅ２Ｏ３。（Ｆｅ（ＯＨ）２沉淀物在空气中老化时则转化为Ｆｅ３Ｏ４．２Ｈ２Ｏ和ＦｅＯＯＨ，两者的相对含量受Ｆｅ＾２＋的迁移速率和Ｆｅ（ＯＨ）２的氧化速度的影响。     

急冷Al－Fe－V－Si－Mm合金的穆斯堡尔谱研究

利用穆斯堡尔谱和Ｘ射线衍射研究了４种Ａｌ－Ｆｅ－Ｖ－Ｓｉ－Ｍｍ合金的Ｆｅ原子组态。结果表明，添加混合稀土元素后抑制了基体合金Ａｌ－Ｆｅ－Ｖ－Ｓｉ中α－Ａｌ１３（Ｆｅ，Ｖ）３Ｓｉ弥散粒子相的析出；当稀土含量高达６ａｔ％时，形成Ａｌ－Ｆｅ－Ｖ－Ｓｉ－Ｍｍ非晶态，采用Ｖｏｉｇｔ基函数作了穆斯堡尔谱的合理拟合和分析。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.