金属卟啉－甲基紫精二连体配合物的合成及其光化学行为

本文合成了四（对－氯代甲基）苯基－甲基紫精卟啉及其Ｚｎ、Ｃｏ、Ｍｎ配合物，用元素分析、红外光谱和紫外可见光谱进行了表征．研究了它们的光化学性质．结果表明．在ＴＥＯＡ中光照使Ｍ·ＴＣＭＰＰ—ｍｖ￣２＋发生了分子内从卟啉到甲基紫精的电子迁移反应．在ＺｎＴＣＭＰＰ－ｍｖ￣２＋／ＴＥＯＡ／ＤＭＳＯ—Ｈ２Ｏ体系中可发生光敏化还原ｍｖ２＋反应，生成较稳定的ｍｖ＋．在Ｍｎ（Ⅲ）ＴＣＭＰＰ－ｍｖ２＋／ＣＨ３ＯＨ／Ｈ２Ｏ体系中可发生光助氧化甲醇反应，并检出了氧化产物甲醛．     

Ni－Cu和TiO_2－SiO_2间的相互作用及其对催化性能的影响

用表面反应改性法制备了ＴｉＯ２－ＳｉＯ２（ＴＳＯ）表面复合物载体．采用ＴＰＲ，ＩＲ，ＴＰＤＭＳ和ＴＰＳＲ－ＭＳ等技术研究了ＮＩ－Ｃｕ／ＴＳＯ间的相互作用及其对ＣＯ加氢反应的催化性能．结果表明，ＮｉＯ－ＣｕＯ与ＴＳＯ间的相互作用导致ＣｕＯ的还原温度降低和ＮｉＯ的还原温度升高，并有少量表面物种生成；还原后的Ｎｉ－Ｃｕ／ＴＳＯ催化剂表面上存在着两类活性中心，即合金相中的Ｎｉ及载体相中的Ｔｉｎ＋（或Ｔｉｎ＋－Ｏ）；ＣＯ在催化剂表面存在孪生、线式、桥式和卧式等４种吸附态；Ｈ２在催化剂表面上发生解离吸附形成Ｎｉ－Ｈ和Ｔｉｎ＋－Ｈ，前者比较活泼，是加氢反应的主要Ｈ源；卧式吸附态极易在催化剂表面裂解形成Ｎｉ－Ｃ和Ｔｉｎ＋－Ｏ，前者是加氢反应的Ｃ源，使ＣＯ加氢生成烃类的反应在Ｎｉ中心上按＂表面碳＂机理进行，其生成乙烯的选择性大于６０％．Ｈ２Ｏ的生成反应在Ｔｉｎ＋中心上按Ｔｉｎ＋－Ｏ与Ｔｉｎ＋－Ｈ或Ｎｉ－Ｈ反应的途径进行．     

Ni/Al2O3催化剂上甲烷部分氧化制合成气反应机理

用变应答／质谱在线检测技术研究了Ｎｉ／Ａｌ２Ｏ３催化剂上甲烷部分氧化制合成气的反应要理，研究结果指出，在常压９７３Ｋ条件下，Ｎｉ／Ａｌ２Ｏ３催化剂上甲烷部分氧化制合成气按直接氧化机理进行，Ｈ２和Ｃ烛甲烷部分氧化的一次产物，其主要反应可表示如下：１．ＣＨ４＋ｘＮｉ－ＮｉｘＣ＋２Ｈ２，２．Ｏ２＋２Ｎｉ－２ＮｉＯ，３．ＮｉｘＣ＋ＮｉＯ－ＣＯ＋（ｘ＋１）Ｎｉ。     

Ni－Cu和MgO－SiO_2间的相互作用及其对催化性能的影响

本文用ＴＰＲ，ＩＲ，ＴＰＤ和ＴＰＳＲ等技术研究了以表面改性法制备的ＭｇＯ－ＳｉＯ２（ＭＳＯ）表面复合物担载的Ｎｉ－ＣＵ合金间的相互作用及其对ＣＯ加氢反应催化性能的影响．结果表明，ＮｉＯ－ＣｕＯ与ＭＳＯ间的相互作用导致部分ＭＯ与ＭＳＯ形成表面物种从而使金属组分氧化物还原温度明显升高；还原后的Ｎｉ－Ｃｕ／ＭＳＯ表面上存在着两类活性中心，即合金相中的Ｎｉ与载体相中的Ｍｇ２＋（或Ｍｇ２＋－Ｏ）；在两类活性中心的协同作用下，ＣＯ吸附除有孪生、线式和桥式吸附态物种外，还有一种新的卧式吸附态（Ｎｉ．．．Ｃ＝Ｏ→Ｍｇ２＋）．这种吸附态的活化程度较高，易在表面上发生裂解形成Ｎｉ－Ｃ和Ｍｇ２＋－Ｏ，其中Ｎｉ－Ｃ是加氢反应的碳源；Ｈ２在催化剂表面上发生解离吸附形成Ｎｉ－Ｈ和Ｍｇ２＋－ＯＨ，前者比较活泼，是加氢反应的氢原．ＣＯ加氢生成烃类的反应在Ｎｉ中心上按＂表面碳＂机理进行，其生成ＣＺＨ４的选择性高于８０％；Ｈ２Ｏ的生成反应按２（Ｍｇ２＋－ＯＨ）－→Ｍｇ２＋＋（Ｍｇ２＋－Ｏ）＋Ｈ２Ｏ方式进行．     

Fe－Mn－K催化剂FT合成反应的研究

研究了Ｆｅ－Ｍｎ－Ｋ催化剂ＦＴ合成动力学及产物分布规律，并探讨了反应条件对（ＣＯ＋Ｈ＿２）转化率及α－己烯／正己烷比的影响。结果表明，该催化剂的产物分布需用两个α才能较好地描述；反应温度及反应气氛下Ｈ＿２／ＣＯ比对α－己烯／正己烷比具有较大影响：最后获得的动力学方程为：－ｒ＿（Ｈ＿２＋ＣＯ）＝ａＰ＿（ＣＯ）Ｐ＿（Ｈ＿２）／（Ｐ＿（ＣＯ）＋ｂＰ＿（Ｈ＿２Ｏ）），从活化能的角度看，该粒度催化剂存在着内扩散效应。     

金属卟啉－甲基紫精二连体配合物的合成及其光化学行为

本文合成了四（对－氯代甲基）苯基－甲基紫精卟啉及其Ｚｎ，Ｃｏ，Ｍｎ配合物，用元素分析、红外光谱和紫外可见光谱进行了表征。研究了它们的光化学性质。结果表明，在ＴＥＯＡ中光照使Ｍ。ＴＣＭＰＰ－ｍｖ＾２＋发生了分子内从卟啉到甲基紫精的电子迁移反应。在ＺｎＴＣＭＰＰ－ｍｖ＾２＋／ＴＥＯＡ／ＤＭＳＯ－Ｈ２Ｏ体系中可发生光敏化还原ｍｖ＾２＋反应，生成较稳定的ｍｖ＾＋。在Ｍｎ（Ⅲ）ＴＣＭＰＰ－ＭＶ＾２＋／ＣＨ３     

连续流动化学发光法测定水中总有机碳的研究

基于Ｋ２Ｓ２Ｏ８氧化水中有机碳为二氧化碳，二氧化碳能增强Ｌｕｍｉｎｏｌ－Ｈ２Ｏ２－Ｃｏ＾２＋体系化学发光强度，建立了连续流动化学光测定水中总有机碳的新方法。方法线性范围为０．１０－１２μｇ／ｍＬＣ，检出限量为０．０４μｇ／ｍＬＣ。所建立方法简便、灵敏，适合于应用于水中总有机碳的测定。     

超高比表面炭载钼煤气甲烷化催化剂

以沥青中间相为原料，氢氧化钾直接活化，获得了比表面达２３６３ｍ￣２／ｇ的超高比表面炭分子筛（ＣＭＳ）。分别以ＣＭＳ、ＳｉＯ＿２、活性炭和θ－Ａｌ＿２Ｏ＿３为担体，制备了负载钼催化剂，并研究其加压甲烷化反应性能，发现活性依下面顺序增加：θ－Ａｌ＿２Ｏ＿３＜ＳｉＯ＿２＜活性炭（ＡＣ）＜ＣＭＳ。还分别以钼酸铵和磷钼酸（ＨＰＭｏ）为前驱体，制备了ＣＭＳ负载钼催化剂，并考察了其煤气甲烷化活性，发现不同的催化剂前驱体对催化剂反应活性影响很大。根据产物中ＣＨ＿４／ＣＯ＿２的变化，推测ＣＯ在钼催化剂上的甲烷化反应包括如下两个步骤：（１）３Ｈ＿２＋ＣＯ→ＣＨ＿４＋Ｈ＿２Ｏ，（２）ＣＯ＋Ｈ＿２Ｏ→ＣＯ＿２＋Ｈ＿２。     

CrO3.CH3NH2.HCl／Al2O3的制备及其对苯偶姻体系的氧化反应

ＣｒＯ３·ＣＨ３ＮＨ２·ＨＣｌ／Ａｌ２Ｏ３的制备及其对苯偶姻体系的氧化反应张贵生＊石启增陈密峰蔡昆（河南师范大学化学系新乡４５３００２）关键词ＣｒＯ３·ＣＨ３ＮＨ２·ＨＣｌ／Ａｌ２Ｏ３，苯偶姻，苯偶酰，氧化１９９６－０８－１８收稿，１９９６－１１－０...     

低碳醇合成Raney Cu－Co催化剂的表征

本文采用ＸＲＤ、ＸＰＳ、及Ｈ_２—ＴＰＤ技术对不同Ｃｕ／Ｃｏ比的几个ＲａｎｅｙＣｕ－Ｃｏ催化剂进行了表征．并与反应醇选择性进行了关联．结果表明：ＲａｎｅｙＣｕ－Ｃｏ催化剂均由不同Ｃｕ／Ｃｏ比的两个Ｃｕ－Ｃｏ固溶体相组成，还原（Ｈ_２，５６３Ｋ，２ｈ）前，表面除有Ｃｕ￣０和Ｃｏ￣０外，尚有少量Ｃｕ￣（＋１）和显著量的Ｃｏ￣（＋２）存在，还原后，Ｃｕ￣（＋１）几乎消失，Ｃｏ￣（＋２）仍有一定量存在，在反应温度下（５６３Ｋ），ＣＯ和ＣＯ_２均能使表面Ｃｏ￣０部分氧化，且ＣＯ_２氧化能力大于ＣＯ，而合成气（Ｈ_２／ＣＯ＝２）表现为还原的性质。三种气氛对Ｃｕ￣０无明显影响。催化剂表面Ｃｕ／Ｃｏ比高于体相Ｃｕ／Ｃｏ比，表面Ｃｕ富集显著．ＲａｎｅｙＣｕ－Ｃｏ催化剂表面有四种吸氢中心：Ｃｕ（弱吸氢中心），高配位Ｃｏ（弱吸氢中心），低配位Ｃｏ（活化吸氢中心），及强吸氢中心；对不同催化剂，表面低配位Ｃｏ中心的比例与醇选择性有一致的变化规律。基于上述结果，就ＣＯ播入中心进行了讨论。     

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.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

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.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.