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固相混合氧化物催化剂用于温和条件下醇液相氧化的研究 总被引:1,自引:0,他引:1
在氧化反应的研究过程中, 利用清洁的氧化剂, 借助于可循环使用的固相材料为催化剂, 使用对环境友好的溶剂体系, 是绿色氧化反应的一个研究方向. 本工作以混合氧化物Ru-Mn-Fe-Cu-O为催化剂, 分子氧为氧化剂, 甲苯为溶剂, 各类醇均可在温和的条件下迅速地转化成相应的羰基化合物. 发现在有表面活性剂存在情况下, 以水为溶剂该催化剂也可将各类醇实现有效氧化转化, 阳离子表面活性剂比其他类型表面活性剂更可促进催化剂-水-表面活性剂所组成的催化氧化性能. 相似文献
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《中国化学》2018,36(1):15-19
An aerobic oxidation of aldehydes towards carboxylic acids in MeCN using 1 atm of pure oxygen or oxygen in air as the oxidant and a catalytic amount of single component catalyst, Fe(NO3)3 · 9H2O, has been developed. Carboxylic acids with different synthetically useful functional groups were obtained at room temperature. Two mechanistic pathways have been proposed based on isotopic labeling, NMR monitoring, and control experiments. The practicality of this reaction has been demonstrated by conducting several 50 mmol‐scale reactions using pure oxygen or an air‐flow of ~30 mL/min. 相似文献
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The catalytic oxidation of benzyl halides to aldehydes and ketones in aqueous media was studied under relatively mild reaction conditions by using phase-transfer catalyst combined with potassium nitrate and 10% aqueous potassium hydroxide solution. As a result, a simple high-yield procedure has been developed. 相似文献
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Selective Aerobic Oxidation of Primary Alcohols to Aldehydes over Nb2O5 Photocatalyst with Visible Light 下载免费PDF全文
Dr. Shinya Furukawa Prof. Dr. Tetsuya Shishido Dr. Kentaro Teramura Prof. Dr. Tsunehiro Tanaka 《Chemphyschem》2014,15(13):2665-2667
Primary alcohols are selectively converted into aldehydes by using a Nb2O5 photocatalyst under visible‐light irradiation. A strong interaction between the alcohol and Nb2O5 generates a donor level within the forbidden band of Nb2O5, which provides a visible‐light‐harvesting ability. Over oxidation of aldehydes into carboxylic acids does not proceed under visible‐light irradiation. 相似文献
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The heterogeneous oxidation of toluene in aqueous medium has been investigated. Artificially contaminated water with aromatic compound (toluene) was exposed to a simple platinized zirconia (1% Pt/ZrO2) catalyst in the presence of molecular oxygen. This selective oxidation of toluene to benzyl alcohol, benzaldehyde and benzoic acid provides a step for removing toluene from wastewater or converting it into less harmful substances. Different parameters, e.g. the reaction time, temperature, pressure, the amount of catalyst and agitation, etc influenced the toluene conversion and selectivity. Typical batch reactor kinetic data were obtained and fitted to the classical Langmuir‐Hinshelwood model, Mars‐van Krevelen model as well as to the Eley‐Rideal model of heterogeneously catalyzed reactions. The Eley‐Rideal model was found to give a better fit. 1% Pt/ZrO2 was observed to be the most active for oxidation of toluene at 333 K in oxygenated atmosphere [p(O2) ca. 101 kPa] with a nominal stirring speed ≧900 r/min. It was found that catalytic oxidation may be an effective method for the removal of volatile organic compounds from aqueous solutions and comparable to other advanced oxidation processes. 相似文献
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Fries Rearrangement of Phenyl Acetate over Solid Acid Catalyst 总被引:1,自引:0,他引:1
A silica-supported zirconium based solid acid (ZS) has been used as catalyst for the Fries rearrangement of phenyl acetate (PA). The catalyst showed a higher PA conversion activity and a much higher selectivity for o-hydroxyacetophenone (o-HAP) than for strongly acidic zeolite catalysts. The supported catalyst was characterized by XRD,IR,XPS,pyridine-TPD and the surface area measurements. The catalytic properties were influenced significantly by pretreatment temperature. 相似文献
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Catalytic oxidation reactions often suffer from drawbacks such as low yields and poor selectivity. Particularly, selective oxidation of alcohols becomes more difficult when a compound contains more than one oxidizable functional group. In order to deliver a methodology that addresses these issues, herein we report an efficient, aerobic, chemoselective and simplified approach to oxidize a broad range of benzyl and propargyl alcohols containing diverse functional groups to their corresponding aldehydes and ketones in excellent yields under mild reaction conditions. Optimal yields were obtained at room temperature using 1 mmol substrate, 10 mol % copper(I) iodide, 10 mol % 4-dimethylaminopyridine (DMAP), and 1 mol % 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) in acetonitrile, under an oxygen balloon. The catalytic system can be applied even when sensitive and oxidizable groups such as alkynes, amines, and phenols are present; starting materials and products containing such groups were found to be stable under the developed conditions. 相似文献
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CuBTC(BTC:1,3,5-均苯三酸)作为一种高效、可重复利用的非均相催化剂,在催化领域有着重要的应用。论文主要研究了在Cu-TEMOP体系下,CuBTC对苯甲醇的需氧氧化反应的催化效果。研究表明,在CuBTC的催化下,多种苯甲醇衍生物被有效的氧化成相应的醛,并且该催化体系有着较高的选择性,能高效氧化伯醇。与传统的均相铜盐催化剂相比,Cu(II)能稳定的固定在CuBTC的刚性结构骨架中,并且催化活性不会降低。但是,羧酸类物质会使CuBTC催化剂中毒,所以CuBTC不适用于原料、产物或者副产物中存在羧酸的反应体系。 相似文献
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In the presence of [Ru(terpyridine)(2,6‐pyridinedicarboxylate)], aliphatic and benzylic alcohols are oxidized to the corresponding aldehydes or ketones with high selectivity by using hydrogen peroxide as the oxidant. There is no need for the addition of co‐catalysts or organic solvents. By applying an optimized reaction protocol, high catalyst productivity (turnover number>10 000) and activity (turnover frequency up to 14 800 h?1) has been achieved. 相似文献
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随着新的全球气候协议下的中国双碳行动计划的实施, 开发和利用可再生生物质资源显得极为重要. 甘油作为生物柴油在生产过程中的主要副产物, 将其催化转化成各种高附加值衍生物受到广泛关注, 其中甘油选择性氧化为乳酸具有巨大的应用前景. 近年来, 采用固体催化剂催化氧化甘油制乳酸成为国内外学者研究的热点. 我们综述了固体催化剂用于甘油催化转化制备乳酸的研究现状, 对甘油催化转化为乳酸的反应途径做了分析, 并讨论了影响催化剂活性的因素, 对当前所存在的问题提出建议, 也对未来相关催化剂制备发展进行了展望. 相似文献
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Kalpana Handore Sanjay Bhavsar Amit Horne Prakash Chhattise Kakasaheb Mohite Jalinder Ambekar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):941-947
ZnO nanoparticles have been synthesized by using biodegradable natural biopolymer viz. Gum Tragacanth. This single step approach is very cost effective and reproducible. The reaction time and concentration of precursor zinc acetate play a major role in the nature and growth of ZnO nanoparticles. ZnO nanoparticles were characterized by X-ray diffraction, SEM, FTIR, EDAX, UV-visible spectroscopy and TEM. ZnO nanoparticles with 20-30 nm in diameter and hexagonal morphology were found; dispersed uniformly. Raman spectrum shows the mode E2 high at 437 cm?1 that is related to the vibration of wurtzite Zn-O bond in crystal structure of ZnO. The space between adjacent lattice fringes is ~ sharp 2.42 Å. UV-visible absorption spectrum shows the sharp absorption band at 308 nm assigned to the intrinsic transition from valance band to conduction band. The ZnO nanoparticles display superior catalytic activity of conversion of aldehyde to acid as compared to bulk-ZnO material, because of high surface area of ZnO nanoparticles. A trace amount of ZnO nanoparticles catalyst required for organic conversion. The ZnO nanoparticles as catalyst are highly stable, recyclable and efficient in its activity. 相似文献
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