树脂法分离纯化邻硝基苯甲醛

本文报道树脂法从混合物中分离纯化邻硝基苯甲醛的方法。研究说明，通过伯胺树脂与醛的反应对邻硝基苯甲醛进行化学吸附，可以将邻硝基苯甲醛从含有邻硝基甲苯、邻硝基苯甲醛、邻硝基溴苄、邻硝基－α，α─二溴苄、以及邻硝基苄醇的混合物中有效地分离出来。     

锇-聚乙烯吡啶复合物与辣根过氧化物酶分子多层膜的制备及电化学性质研究

基于分子间静电相互作用力,将锇-聚乙烯吡啶复合物(PVP-Os)与辣根过氧化物酶(HRP)交替沉积于固体基质表面,制得了包含生物成分的分子多层膜.膜层间的聚合物分子起到了粘接与导电的双重作用.用紫外-可见光谱法跟踪了石英基片上的组装过程,研究了多层膜电极对过氧化氢的电催化还原性能,并描述了多层膜电化学行为.     

利用层层自组装技术制备聚电解质多层膜高效液相色谱固定相

以聚(乙烯-alt-马来酸)的苯乙胺衍生物与聚烯丙基胺盐酸盐为原料,通过层层自组装技术(LBL)在色谱硅胶表面交替沉积得到聚电解质多层膜高效液相色谱(HPLC)固定相;利用紫外光谱、红外光谱和元素分析研究了HPLC固定相的结构和组成.结果表明,聚电解质多层膜HPLC固定相被成功构筑在硅胶颗粒表面;制备的多层膜固定相可方便地用于6种芳香烃类及4种烷基苯类物质的分离分析.本文的研究结果说明LBL技术在制备HPLC固定相方面具有一定的应用价值.     

2-硝基-5-(N-甲基-N-十八烷基)氨基苯甲酸多层膜的制备和性质

用2-硝基-5-(N-甲基-N-十八烷基)氨基苯甲酸(NMOB)和花生酸制备了200层的交替多层膜,测得其二次谐波信号强度与NMOB层数的平方成正比.论文着重讨论了NMOB的Y型膜和它与花生酸的交替膜中的取向,并对两者之间的不同作了初步的解释.     

层层静电自组装构筑壳聚糖/磷钨酸复合膜的研究

将正电荷的壳聚糖与负电荷的磷钨酸溶液通过静电作用交替沉积在基底上组装复合多层膜。使用紫外可见光谱(UV-Vis)、红外光谱(FTIR)、X-射线光电子能谱(XPS)、原子力显微镜(AFM)和循环伏安法(CV)等手段对复合膜进行了表征。UV-Vis结果显示多层膜在特征吸收峰处的吸光度数值随膜双层数增加逐渐增大，呈良好的线性关系，表明多层膜是均匀组装的；XPS和FTIR结果证实了壳聚糖和磷钨酸被组装到膜上，AFM图形显示膜表面有一定的粗糙度，CV结果说明多层膜保留了磷钨酸的电化学性质。     

表面印迹交替层状组装薄膜

在简要概述非常规交替层状组装这一进展后,重点总结了如何利用非常规交替层状组装以实现表面印迹膜的制备.模板分子与聚电解质在溶液中组装形成超分子复合物,然后以此超分子复合物为构筑基元,与感光性高分子,如重氮树脂,通过常规交替层状组装形成聚合物多层膜.利用聚合物多层膜之间的光化学反应形成稳定的多层膜,然后去除模板分子得到分子...     

纳米尺度氧化石墨烯层作为高效碳催化剂用于苄醇与芳香醛的绿色氧化

合成了纳米尺度氧化石墨烯(NGO)层,用作碳催化剂高效催化苄醇与芳香醛的氧化反应.对于醇氧化反应,当80℃时H2O2存在下,NGOs(20 wt％)可高效催化醇选择性生成醛,其反应速率和产率取决于醇上取代基的性质.对于4-硝基苄醇,反应24 h后,只有10％可转换为相应羧酸.相反,4-甲氧基苄醇和二苯基甲醇分别反应仅9和3h则可完全转化为对应的羧酸和酮.NGO碳催化剂上芳香醛氧化速率高于醇氧化速率.对于所有的醛,采用7 wt％ NGO作催化剂,在70℃反应2-3 h后,就可完全转化为相应羧酸.我们讨论了NGO催化剂结构对苄醇和芳香醛氧化反应影响的可能机理.     

2-硝基-5-(N-甲基-N-十八烷基)氨基苯甲酸多层膜的制备和性质

用2-硝基-5-(N-甲基-N-十八烷基)氨基苯甲酸(NMOB)和花生酸制备了200层的交替多层膜, 测得其二次谐波信号强度与NMOB层数的平方成正比。论文着重讨论了NMOB的Y型膜和它与花生酸的交替膜中的取向, 并对两者之间的不同作了初步的解释。     

纳米尺度氧化石墨烯层作为高效碳催化剂用于苄醇与芳香醛的绿色氧化（英文）

合成了纳米尺度氧化石墨烯(NGO)层,用作碳催化剂高效催化苄醇与芳香醛的氧化反应.对于醇氧化反应,当80℃时H_2O_2存在下,NGOs(20 wt%)可高效催化醇选择性生成醛,其反应速率和产率取决于醇上取代基的性质.对于4-硝基苄醇,反应24 h后,只有10%可转换为相应羧酸.相反,4-甲氧基苄醇和二苯基甲醇分别反应仅9和3h则可完全转化为对应的羧酸和酮.NGO碳催化剂上芳香醛氧化速率高于醇氧化速率.对于所有的醛,采用7 wt%NGO作催化剂,在70℃反应2-3h后,就可完全转化为相应羧酸.我们讨论了NGO催化剂结构对苄醇和芳香醛氧化反应影响的可能机理.     

交联壳聚糖水凝胶填充层状微胶囊的制备与性能

在甲基丙烯酸和乳酸接枝修饰的水溶性壳聚糖(CML)存在下, 合成了尺寸均匀的球形CML杂化碳酸钙微粒. 通过层层组装(LBL)技术在该微粒表面形成了聚苯乙烯磺酸钠(PSS)/聚烯丙基胺盐酸盐(PAH)多层膜, 去除碳酸钙微粒后得到内部含有CML的聚电解质微胶囊. 进一步采用紫外光引发CML聚合, 将CML转化为CML微凝胶, 得到内部填充凝胶的微胶囊. 通过扫描电镜、光学显微镜和透射电镜等技术表征了微胶囊的结构. 与传统的LBL微胶囊不同, 凝胶填充的微胶囊干燥时尺寸收缩, 但仍可保持球形; 再次水化后, 能够膨胀恢复其原有尺寸和形态. 各种具有不同电荷性质、分子量和亲疏水性的染料分子及蛋白质均可有效地装载到微胶囊内.     

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.