The efficient synthesis of (3R,4R,5R)-3-amino-4,5-dimethyl-octanoic acid, a chiral β-amino acid with potent affinity for the α2δ protein

A chiral β-amino acid containing three contiguous chiral centers was synthesized efficiently in 11 steps, employing enantio-enriched β-ketoester as a key intermediate, via stereoselective catalytic hydrogenation of the corresponding enamide. Stereoselective 1,4-addition of a methyl group and protonation were key to the preparation of the desired acid 12. Mild and efficient reaction conditions were applied to the enamine formation and protection to avoid epimerization at C-4 of compounds 13 and 14. The final compound was found to display potent affinity for the α₂δ-protein that is a recognized drug target for the treatment of a variety of diseases.     

蒙皂族粘土基催化材料的设计制备和催化作用

较全面地评述了蒙皂族粘土矿物层间催化活性组分的设计制备及其催化应用的研究新进展.2:l型层状结构的蒙皂族粘土具有层间阳离子的可交换性和活性物种的可嵌层性,使层间设计和构造催化活性中心极具灵活性.迄今在蒙皂族粘土层间可设计制备的物种有金属阳离子、金属单质、金属氧化物及复合氧化物、金属络合物、金属硫化物和碳等.作为一类主客体纳米复合催化材料,对层间物种的分布和微结构的深入认识,进而能精确调控,是开发和应用此类材料的关键和难点.蒙皂族粘土基催化材料已在氧化、脱水、加氢、裂化、异构化和烷基化等催化反应中显示出工业应用前景.最后,评述了该领域尚存在的若干科学问题和发展方向.     

Oxidation of NO over cobalt oxide supported on esoporous silica

Cobalt oxide catalysts supported on mesoporous silica (Co3O4/MPS) were prepared, characterized and applied for catalytic oxidation of NO. Effects of catalyst supports, calcination temperatures, H2O and SO2 on NO conversion were investigated. The samples were also characterized by BET, XRD, FTIR and TG/DTG. The results suggested that Co3O4/MPS catalyst calcined at 573 K had the smallest crystal particles and the best surface dispersion. This catalyst had the highest activity and yielded 82% NO conversion at 573 K, at a space velocity of 12000 h−1. Although the conversion of NO decreased with the introduction of H2O, it could be restored completely after removing residual H2O from Co3O4/MPS catalyst by heating at 573 K. In the presence of SO2, the oxidation activity decreased and CoSO4 was detected on the catalyst. The NO conversion decreased to 30.2% in the presence of SO2 and H2O. It could not be restored completely after cutting off H2O and SO2. The deactivation of the catalyst in the presence of SO2 and H2O was attributed to the formation of cobalt sulfate species.     

电化学催化氧化降解含酚废水的研究进展

酚类化合物具有高毒性,难降解性,国内外研究者越来越重视含酚废水的治理.电化学催化氧化技术在降解酚类化合物方面的研究较多.作者深入探讨了电化学催化氧化技术降解酚类化合物的机理和历程,概述了一些常用阳极材料的优缺点,最后指出了该技术存在的一些问题与发展前景.     

铜(Ⅱ)及其配合物催化胆红素氧化动力学的研究

本文用电化学，吸收光谱等方法对Ｃｕ（２＋）及其配合物与胆红素在碱性（ｐＨ１０）条件下的作用规律进行了研究．发现Ｃｕ（２＋）及其配合物对胆红素的氧化的催化作用依配合物的稳定性和配体齿数不同而异．在胆红素的氧化过程中，真正起氧化作用的是溶解氧．     

Laccase

The present review was dedicated to laccase—the enzyme, belonging to the group of multinuclear copper, containing so called “blue” oxidases. The molecular structure, metals content, substrate specificity, and other physicochemical properties were described in this article. The authors considered the mechanism of enzymatic action and electrocatalytic oxygen reduction catalyzed by laccase in details. The data of laccase application in organic synthesis, biosensors, and immunoenzyme assay were presented.     

氯酸钾－二甲基黄－钒（Ⅴ）体系催化光度法测定痕量钒

本文研究了氯酸钾－二甲基黄－钒（Ⅴ）体系催化光度法测定痕量钒的条件及应用。钒含量在０～６０ｎｇ／１０ｍＬ范围内与ｌｇ（Ａ＿０／Ａ）有良好的线性关系，检出限１．０×１０￣（－１１）ｇ／ｍＬ。方法简便快速，应用于水及食品中痕量钒测定，结果满意。     

萃取催化动力学分析法测定痕量钯

本文研究了在ｐＨ３．Ｏ的缓冲溶液中，利用邻菲罗嘛活化Ｐｄ（Ⅱ）催化水中溶解氧氧化二苯硫腙褪色的指示反应，建立了测定痕量钯的萃取催化动力学分析方法。方法的灵敏度为３．３×１０￣（－９）ｇ／ｍＬ，线性范围为７．５×１０￣（－９）～４．０×１０￣（－７）Ｇ／ｍＬ。用于钯催化剂中钯的测定，获得了满意的结果。     

REUSY中部分非骨架铝对酸中心的掩蔽作用

藉助于低温氮吸附、ＮＨ_３－ＴＰＤ和脉冲微反（正庚烷裂解及邻二甲苯转化）等技术研究了ＲＥＵＳＹ中被稀盐酸浸取出的非骨架铝碎片对其孔结构、酸性及催化活性的贡献。结果表明，该部分非骨架铝大部分填充在沸石二次孔中，少量沉积在沸石微孔中。稀盐酸浸取后，样品的酸中心强度及酸量均有所增大，正庚烷裂解和邻二甲苯转化活性明显提高，依此认为，该部分非骨架铝碎片对酸中心具有一定的掩蔽作用。     

Preparation of ordered mesoporous TiO2 thin film and its application in methanol catalytic combustion

Ordered mesoporous titania thin films were synthesized by evaporation induced self‐assembly process in the presence of Pluronic block copolymers P123 (EO₂₀‐PO₇₀‐EO₂₀). The influence of several experimental parameters, including aging humidity, aging temperature, substrate properties and methods for organic templates removal, on the mesostructure of titania thin films was investigated in details. The mesoporous titania thin film supported Pt catalyst was prepared, and its methanol catalytic combustion performance was studied. The results showed that mesoporous titania thin film is an active support for catalyst. Mesoporous titania thin film supported platinum catalysts yields 70% methanol conversion at room temperature and 100% conversion at 100 °C. Copyright © 2013 John Wiley & Sons, Ltd.