中性条件下亚氯酸钠和双氧水氧化芳香醛

本文优化了中性环境中亚氯酸钠和双氧水氧化醛的反应条件,采用正交实验设计法考察了溶剂、亚氯酸钠和双氧水的用量以及反应温度对醛氧化产率的影响,确定最佳工艺条件为以乙醇作溶剂,亚氯酸钠、双氧水、醛的摩尔比为1.1:2:1。在优化的反应条件下对醛进行底物扩展验证其适应性,并通过放大实验说明其工业生产适用性,本方法具有产率高、后处理简单、副产物绿色无污染的优点。     

间位苯基桥联的锰(Ⅲ)双咔咯的合成、表征及催化氧化性质(英文)

通过间苯二甲醛与5-氟苯基二吡咯甲烷反应合成了一种新的间位苯基桥联的双咔咯1,并利用锰盐与自由咔咯反应制备了其锰的金属配合物2。采用紫外、质谱、核磁、XPS等手段对化合物进行了表征。以苯乙烯为底物考察了锰双咔咯2的催化氧化性质,探讨了时间、溶剂、氧源、轴向配体对催化反应的影响。结果表明以亚碘酰苯和间氯过氧苯甲酸为氧源时催化的主要产物为环氧苯乙烷,而以双氧水和叔丁基过氧化氢为氧源时则主要产物为苯甲醛;在极性溶剂中的催化氧化产率较高。轴向配体对催化氧化有促进作用,不同轴向配体对催化反应产率提高的顺序是:1-甲基咪唑吡啶咪唑。     

四正丁基过硫酸铵氧化裂解2，4-二硝基苯腙衍生物的反应研究

四正丁基过硫酸铵在1,2二氯乙烷溶剂中可高产率地使醛和酮的2,4-二硝基苯腙衍生物氧化裂解成相应的羰基化合物,其分子中碳碳双键,氰基,酯基和缩醛基等基团均不受影响。同时探讨了可能的反应机理和反应溶剂对氧化裂解反应的影响。     

新型催化剂钛硅中空微球催化氧化N-甲基吗啉

N-甲基氧化吗啉(NMMO)是纤维素的优良溶剂,本文首次以合成的具有中空结构的钛硅微球作为催化剂,以双氧水为氧化剂,将N-甲基吗啉氧化为NMMO的新工艺,考查了原料配比、反应温度、反应时间、催化剂钛硅含量等实验条件对产率的影响.用SEM、IR、TEM等手段对催化剂的形貌及结构进行了表征;得出的最佳工艺条件是:反应最佳温度为70℃,原料最佳质量配比为1.30∶1.61(N-甲基吗啉∶双氧水),反应时间6小时,选用含钛量5%的钛硅中空微球作催化剂,产率达到89%.     

苄基咪唑氯镍酸盐的合成,结构及催化醛醇酯化

合成了三种苄基咪唑氯镍酸盐,通过红外光谱、元素分析、核磁共振(1H NMR)以及X-射线单晶衍射对其结构进行了表征,并研究了其在醛醇酯化反应中的催化活性。催化研究结果表明,在优化条件下,苄基咪唑氯镍酸盐对醛醇酯化反应有着较好的催化活性,以对甲基苄基咪唑氯镍酸盐为催化剂,通过一步氧化酯化路线可以有效地催化氧化苯甲醛进行酯化反应,产率为80 %。     

间位苯基桥联的锰（Ⅲ）双咔咯的合成、表征及催化氧化性质

通过间苯二甲醛与5-氟苯基二吡咯甲烷反应合成了一种新的间位苯基桥联的双咔咯1,并利用锰盐与自由咔咯反应制备了其锰的金属配合物2。采用紫外、质谱、核磁、XPS等手段对化合物进行了表征。以苯乙烯为底物考察了锰双咔咯2的催化氧化性质,探讨了时间、溶剂、氧源、轴向配体对催化反应的影响。结果表明以亚碘酰苯和间氯过氧苯甲酸为氧源时催化的主要产物为环氧苯乙烷,而以双氧水和叔丁基过氧化氢为氧源时则主要产物为苯甲醛;在极性溶剂中的催化氧化产率较高。轴向配体对催化氧化有促进作用,不同轴向配体对催化反应产率提高的顺序是：1-甲基咪唑 >吡啶 >咪唑。     

苄基咪唑氯镍酸盐的合成、结构及催化醛醇酯化反应活性研究

合成了三种苄基咪唑氯镍酸盐,通过红外光谱、元素分析、1H NMR以及X-射线单晶衍射对其进行结构表征,并研究了其在醛醇酯化反应中的催化活性。结果表明,在优化条件下,苄基咪唑氯镍酸盐对醛醇酯化反应有着较好的催化活性,以1,3-二(4-甲基苄基)咪唑鎓氯镍酸盐为催化剂,通过一步氧化酯化路线可以有效地催化氧化苯甲醛进行酯化反应,产率为80%。     

大孔型聚合物氧化三甲胺的制备及其氧化卤代烃成醛的研究

本文以D301大孔弱碱性阴离子交换树脂为原料制备了一种稳定的氧化树脂——大孔型聚合物氧化三甲胺,并研究了其氧化各类卤代烃成醛的反应。实验结果表明:该氧化树脂能在温和条件下将伯碘代物、伯溴代物、烯丙基型卤代物及苄基卤代物高产率地氧化成醛;用该氧化树脂氧化双溴代物可得到良好产率的单醛;当同一化合物中卤原子和其它官能团共存时,该氧化树脂可对其中的卤原子进行选择性氧化。反应后的树脂可完全再生,重复使用三次后树脂的活性没有明显的降低。     

室温下以水为溶剂的双氧水氧化苯甲醇制备醛的绿色化反应设计

通过环境友好、价格便宜的铁配合物,在室温下催化以水为溶剂的双氧水氧化苯甲醇制备醛的反应,是典型的绿色醇氧化法。同时,原位制备的催化剂不仅具有高效催化活性,而且选择性强,有效地避免苯甲醛的过度氧化产生苯甲酸。     

苄氯制备苯甲腈工艺的改进

研究了一锅法苄氯经氨化和碘氧化制备苯甲腈工艺的绿色化改进。实施了三氧化钼催化双氧水氧化碘离子以实现碘的循环使用而完善了后处理;在高压反应釜中优化工艺条件,提高苯甲腈产率到82%以上,碘的回收率都在98%以上,实现了碘的循环使用。该改进工艺反应条件温和、产率高和低成本以及环境友好,具有工业应用价值。     

An environmentally benign route for epichlorohydrin from allyl chloride epoxidation catalyzed by heteropolyphosphatotungstate

In the absence of organic solvent, allyl chloride was epoxidized with aqueous hydrogen peroxide catalyzed by a heteropolyphosphatotungstate catalyst with very good activity and recycling activity. Under optimized conditions, an epichlorohydrin yield of 88.7% was achieved in the first run; after two recycles, the epichlorohydrin yield remained still above 85.0%. Various factors affecting the catalytic reaction were investigated systematically. The reaction rate of hydrogen peroxide in the epoxidation of allyl chloride is zero order with respect to hydrogen peroxide. The activation energy is 52.27 kJ/mol.     

Epoxidation by sodium chlorite with aldehyde-promoted chlorine dioxide formation

An improved method is described for selective room temperature epoxidation of alkenes by sodium chlorite in a solvent mixture of ethanol, acetonitrile, and water buffered at pH 7. In addition, the use of aldehydes as promoters in chlorite oxidations is described for the first time. The amount of sodium chlorite, the solvent mixture, and the addition of formaldehyde as a practical promoter were optimized. Styrene was used as a test substrate in the optimization studies and the generality of the method was assessed by using a variety of nucleophilic and electrophilic substrates. Yields up to 89% were obtained with styrene and other nucleophilic alkenes are readily converted into epoxides.     

钨过氧酸盐离子液体催化过氧化氢氧化苯甲醇制苯甲酸

用甲基三辛基氯化铵和钨酸钠一步法合成甲基三辛基季铵钨酸盐离子液体[(CH3)N(n-C8H17)3]2W2O11,以该离子液体为催化剂,在无反应溶剂条件下催化过氧化氢氧化苯甲醇生成苯甲酸。 考察了反应温度、催化剂用量以及氧化剂过氧化氢用量对苯甲酸产率的影响。 确定优化条件：反应温度70 ℃,苯甲醇用量5 mmol,催化剂用量是底物的0.4%(摩尔分数),30%过氧化氢用量2 mL,苯甲醇的转化率可达99%,苯甲酸选择性为98%。 该方法具有反应条件温和、产率高和选择性好的优点。     

磷钨杂多酸盐催化的氯丙烯水油两相条件下的环氧化

研究了磷钨杂多酸盐对氯丙烯与H2O2水溶液两相条件下环氧化反应的催化活性.反应结果表明,环氧氯丙烷的产率受溶剂二氯乙烷量影响;二氯乙烷作溶剂时,这一反应体系具有很好的催化性能,环氧氯丙烷产率可达88.3%;甲苯不是氯丙烯环氧化的优良溶剂.     

NaY型沸石分子筛催化环己胺氧化制备环己酮肟

考察了系列氧化剂、催化剂和溶剂对环己胺液相氧化制备环己酮肟的影响,发现以乙腈为溶剂,过氧化氢为氧化剂,NaY型沸石分子筛对该反应具有优良的催化性能。 对该反应体系进行了五因素四水平的正交实验,确定了适宜的催化剂用量、溶剂用量、反应时间、反应温度和氧化剂用量,比较分析了各因素对环己胺转化率和环己酮肟选择性的影响。 确定了环己胺液相氧化反应的最佳工艺条件为：环己胺为3 mL,催化剂为03 g,环己胺、溶剂和氧化剂的体积比为1∶3∶3,65 ℃反应2 h。 讨论了环己胺液相催化氧化的反应机理。     

A UNIQUE ALDEHYDE CHEMILUMINESCENCE INVOLVING PEROXIDE AND COPPER I IN ACIDIC DMSO

Simple aliphatic aldehydes, when mixed with hydrogen peroxide in acidic, aprotic solvents containing copper I, chemiluminesce weakly. The reaction is very specific for copper I. Quantum yield determinations reveal a catalytic role for copper I and a 1:1 stoichiometry for aldehyde and hydrogen peroxide. Kinetics reveal that an aldehyde/peroxide adduct is the active compound and synthetic l-hydroxy octyl hydroperoxide is completely active in the reaction. Similarities in substrates. kinetics and insensitivity to extraneous substances suggest this reaction as a model for earthworm bioluminescence.     

用双氧水绿色氧化环己酮合成己二酸的研究

以30%的双氧水为氧化剂, 钨酸钠与含N或O的双齿有机配体(草酸)形成的络合物为催化剂, 在无有机溶剂、无相转移剂的条件下, 研究了环己酮氧化制己二酸的反应. 研究结果表明, 用廉价的草酸为配体, 最佳反应条件为钨酸钠∶草酸∶环己酮∶30%的双氧水的物质的量比为2.0∶3.3∶100∶350, 在92 ℃下反应12 h, 可制得80.6%的己二酸; 用GC-MS跟踪了氧化过程中三种主要物质环己酮、己内酯及己二酸含量随反应时间的变化关系, 提出了其主要氧化机理为环己酮首先经Beayer-Villiger氧化反应生成己内酯, 己内酯进一步氧化成己二酸.     

5-Amino-4-sulfanylphthalhydrazide as a chemiluminescence derivatization reagent for aromatic aldehydes in liquid chromatography

5-Amino-4-sulfanylphthalhydrazide (ASPH) was synthesized as a chemiluminescence derivatization reagent for aromatic aldehydes in liquid chromatography (LC). Benzaldehyde, 4-tolualdehyde, 4-chlorobenzaldehyde, 4-formylbenzoic acid, 4-hydroxybenzaldehyde and vanillin were used as model compounds to optimize the derivatization conditions. This reagent, ASPH, reacts selectively with aromatic aldehydes in the presence of sodium sulfite and disodium hydrogenphoshite in acidic medium at 100 degrees C to give the corresponding highly chemiluminescent 2-arylbenzothiazole derivatives. The resulting derivatives generated intense chemiluminescence by reaction with hydrogen peroxide and potassium hexacyanoferrate(III) in alkaline solution. The ASPH derivatives of aromatic aldehydes were separated by reversed-phase liquid chromatography with isocratic elution, and detected chemiluminometrically after mixing with oxidizing agents. The detection limits (signal-to-noise ratio = 3) for aromatic aldehydes are in the range 0.2-4.0 fmol for a 20-microl injection volume. Currently, the method is not effective for aliphatic aldehydes because of interfering LC peaks.     

Efficient synthesis of triarylmethanes via bisarylation of aryl aldehydes with arenes catalyzed by silica gel-supported sodium hydrogen sulfate

An efficient synthesis of triarylmethanes has been developed via bisarylation of aryl aldehydes with arenes catalyzed by silica gel-supported sodium hydrogen sulfate in a solvent-free system. The new method features high yield, mild reaction conditions, and environmental friendliness.     

Oxidation of aldehydes to carboxylic acids in water catalyzed by cobalt(II) Schiff-base complex anchored to SBA-15/MCM-41

Cobalt(II) Schiff-base complexes were successfully anchored to SBA-15/MCM-41 and used as a catalyst for the oxidation of aldehydes to afford carboxylic acids in water under the action of hydrogen peroxide. Reaction conditions, such as different catalyst type, reaction temperature, reaction time, solvents media, and catalyst amount were studied systematically. High yield (up to 98%) of the process was reached. Such substrate-supported catalyst can be reused up to five times without significant loss of its catalytic activity which is not lower than 85%.