SYNTHESIS OF FUNCTIONAL MACROMOLECULE INTERMEDIATE THROUGH ACYLATION CATALYZED BY [Emim]Cl-AlCl3 IONIC LIQUID

Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1↑HNMR and FTIR analysis. The influences of various parameters, such as the contents of AlCl3 in [Emim]Cl-AlCl3, the amount of acylation agent, amount of [Emim]Cl-AlCl3, reaction temperature and reaction time were investigated. The optimum conditions were as follows： the molar fraction of AlCl3 in ionic liquid [x（AlCl3）] being 0.67, molar ratio of ionic liquid to anthracene being 2：1, molar ratio of oxalyl chloride to anthracene being 2：1, reaction temperature being 40℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more, [Emim]Cl-AlCl3 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused.     

Catalyst-free synthesis of 3-substituted-3-hydroxy-2-oxindoles by reaction of isatin and cyclic enaminone in water

An easy protocol for the synthesis of enaminone attached 3-substituted-3-hydroxy-2-oxindoles has been demonstrated by reaction of isatin and cyclic enaminone in water. The developed catalyst-free reaction has the advantage of being atom-economical, eco-friendly, and benign reaction conditions. The broader substrate scope, experimentally simple procedures, and easy purification of products with high yield further make this method attractive and useful.     

SYNTHESIS OF FUNCTIONAL MACROMOLECULE INTERMEDIATE THROUGH COUPLING REACTION CATALYZED BY [bmim]Cl/FeCl3 IONIC LIQUID

To obtain new functional aromatic polymer material. 3.3'-biacenophthene. which is used as macrotnolecule intermediate of function aromatic polymer material. was synthesized through the coupling reaction of acenaphthene catalyzing by ionic liquid (/bmim/Cl/FeCl3) at mild reaction condition. Pure 3,3' -biacenaphthene was obtained by recrystalling and column chromatography from the reaction mixture, and was determined by GC/MS. 1HNMR and FTIR analysis. The influence of various reaction conditions on the yield of 3,3'-biacenaphthene were studied by GC analysis. The result shows that the optimun synthesis conditions of the coupling reaction are as following: the molar ratio of FeCl3 to [Bmim]Cl being 3. the mole ratio of FeCl3 in [Bmim]Cl/FeCl3 to acenaphthene being 4. the reaction temperature being 20 ℃, the reaction time being 4h and the solvent of the reaction system being PhNO2. Under those conditions, the yield of the 3,3'-biacenaphthene will be 48.71% and selectivity of that will be 78.56 %. Further more.[bmim ]Cl/FeCl3 has no pollution to environments and can be reused.     

硝基苯的制备及废硫酸回收利用的研究

苯在四氯化碳溶剂中以硝酸和疏酸的混合酸为硝化剂在温和条件下进行硝化，硝基苯的产率高，硫酸可以回收再利用。例如，在带有搅拌器、滴液漏斗、温度计和冷凝器的四颈烧瓶中，加入４４．４毫升苯和４０毫升四氯化碳，将３９．５毫升浓硝酸和４１．５毫升浓硫酸混合后从滴液漏斗中滴加，维持温度在１５～５５℃之间，约４０分钟滴完后，在５５～６２℃继续反应３０分钟。有机层分别用水、１０％氢氧化钠溶液、水洗涤，干燥、蒸馏，先蒸出溶剂可再用。然后收集２０４～２１０．８℃的馏份，得硝基苯６０．６克，产率９８．５３％。废硫酸通过蒸馏浓缩后，可重新用于硝化反应。     

Note Phenomenology and Kinetics of the Reaction Between Sulfur and Atactic Polypropylene

While sulfur has been widely used as a dehydrogenating agent, in particular to obtain conjugated dienes [1-4], there is no kinetic information available about its effect on atactic polypropylene (APP), only Dontsov et al. [5] mentioning the products of this reaction, while Stefanovskaya et al. [6] studied the kinetics of the rather similar reaction with tetrachloro-o-benzoquinone. Also worth mentioning are the kinetic studies carried out by Dontsov et al. [7-11] on the reaction kinetics of polyethylene with sulfur, unsaturation, crosslinks, and mercaptides being the main products and the processes being first-order with activation energies of approximately 120 kJ/mol.     

Kinetics and mechanisms of the permanganate oxidation of L-valine in neutral aqueous solutions

The permanganate oxidation of L-valine has been studied by visible spectrophotometry in neutral aqueous solutions. Under these conditions, both the zwitterionic and anionic forms of the amino acid are oxidized, the reaction being autocatalyzed by soluble colloidal manganese dioxide. Kinetic data for both the uncatalyzed and autocatalytic reaction pathways have been obtained, and reaction sequences consistent with the experimental findings are proposed.     

Unexpected course of Wittig reaction when using cinnamyl aldehyde as a substrate

When trans-cinnamyl aldehyde was used as a substrate of the Wittig reaction, instead of the olefination product, formation of four products with (E)-1,3-diphenylprop-2-en-1-ol and cinnamyl alcohol was observed being quite unexpected ones. The possible mechanism of this unusual reaction has been considered.     

Paradigm confirmed: the first use of ionic liquids to dramatically influence the outcome of chemical reactions

It has been an unproven paradigm that the choice of which ionic liquid to use in a chemical reaction can have a dramatic effect on the outcome of that chemical reaction. We demonstrate, for the first time, that the reaction of toluene and nitric acid in three different ionic liquids gives rise to three completely different products in high yield. Furthermore, ionic liquids can catalyze these reactions with the only byproduct being water. [reaction: see text]     

分散蓝2BLN染料的二氧化氯氧化脱色研究

我们用CIO2氧化分散蓝2BLN,对其进行脱色,在1分钟内脱色率为90％以上。在最佳条件下,研究了反应的动力学。用PMS半经验方法计算了2BLN分子的键级。结果表明,脱色反应的级数,对2BLN为1级,对CIO2为0．5级,这个反应是十分快的,开始于一个Sn2亲核历程。     

Asymmetric organocatalytic N-nitroso-aldol reaction of oxindoles

An organocatalytic enantioselective N-nitroso-aldol reaction of 2-oxindoles promoted by a cinchona alkaloid catalyst has been developed. The reaction shows exclusively N-selectivity, affording corresponding products with good to excellent yields (up to 100%) and moderate enantioselectivity. The regioselectivity of nitroso-aldol reaction being controlled by different cinchona catalysts was also observed.     

阻燃PVA-g-AN的制备、表征及性能

以K₂S₂O₈-NaHSO₃氧化还原体系为引发剂, 将丙烯腈(AN)接枝到聚乙烯醇(PVA)上, 得到聚乙烯醇接枝丙烯腈聚合物(PVA-g-AN), 将其与磷酸-尿素反应制备阻燃聚乙烯醇接枝丙烯腈聚合物(FR-PVA-g-AN). 利用傅里叶变换红外光谱(FTIR)、 X射线能谱(XPS)和X射线衍射(XRD)对其结构进行表征, 并用热重分析(TGA)对其热性能进行研究. 结果表明, 当引发剂用量占反应物总质量的1%, n(K₂S₂O₈):n(NaHSO₃)=5:1, m(丙烯腈):m(聚乙烯醇)=3.5:1, 70 ℃反应4 h时, 接枝率可达190%; 在m(磷酸):m(尿素)=5:1, 85 ℃条件下处理接枝产物PVA-g-AN 4 h时, 获得阻燃性能良好的FR-PVA-g-AN, 700 ℃马弗炉热处理后, 残炭量达到63%. TGA结果显示, FR-PVA-g-AN的热降解过程较PVA减慢, 且800 ℃后残炭量由PVA的3.12%增加到54.3%, 说明FR-PVA-g-AN具有优异的热稳定性和成炭性.     

Reaction of alkyl splitting of 4-acetylamino-N-(3,5-di-tert-butyl-4-hydroxybenzyl)-benzenesulfonamide

Russian Journal of General Chemistry - Alkyl splitting of 4-acetylamino-N-(3,5-di-tert-butyl-4-hydroxybenzyl)benzenesulfonamide with alkali solution has been discovered, the reaction being uncommon...     

Kinetic study of the oxidation of L-phenylalanine by potassium permanganate in acid medium

The kinetics of permanganate oxidation of L-phenylalanine in acid medium at a constant ionic strength has been investigated spectrophotometrically. An autocatalytic reaction was observed being autocatalyzed by a soluble form of Mn(IV). The reaction appears to involve a parallel consecutive reaction process in which Mn(IV) is formed as an intermediate and Mn(II) as a reaction product. A tentative mechanism consistent with the kinetics is discussed. © 1995 John Wiley & Sons, Inc.     

Correlation of relative rates of PdCl(2) oxidation of functionalized acyclic alkenes versus alkene ionization potentials, HOMOs, and LUMOs.

Investigations of the title reaction, carried out by plotting logs of the relative reaction rates vs IPs, vs HOMOs, and vs LUMOs, reveal multiple nearly parallel lines of correlation with small negative slopes in each. Overall, the natural grouping into monosubstituted and disubstituted alkenes gives better correlations than that obtained by using all alkenes. Comparison with analogous plots for other reactions indicates that the mechanism for this reaction has similarities to that for hydroboration, the major difference being that the lines in the plots for hydroboration have positive slopes, indicating an electrophilic rate-determining step involving the pi electrons, while those for the title reaction have small negative slopes, indicating a nucleophilic rate-determining step. Of the two reaction mechanisms proposed for the title reaction, only one has a nucleophilic attack at the complexed alkene as the rate-determining step, and therefore, this work supports that reaction mechanism.     

Pd-catalyzed allylic substitution using nucleophilic N-heterocyclic carbene as a ligand

A nucleophilic N-heterocyclic carbene has been successfully used in a Pd(0)-catalyzed allylic substitution for the first time. It was found that allylic substitution with a soft nucleophile using a Pd-carbene catalyst proceeds via retention of configuration, the stereochemical reaction pathway being the same as that of the reaction using a Pd-phosphine complex. [reaction--see text]     

Preparation of a PEG‐Supported Ligand as Highly Stable Palladium Catalyst and Its Efficient Recyclability in the Heck Reaction

A reagent of NNN ligands immobilized on PEG has been prepared and coordinated to Pd(OAc)₂ to provide a highly efficient and recyclable catalysis system for the Heck reaction. The reaction works very well with this catalysis system, and no palladium black is observed during the reaction. The reagent and palladium can be recycled easily and do not show significant activity decay after being reused 10 times.     

Highly stereoselective chemoenzymatic synthesis of the 3H-isobenzofuran skeleton. Access to enantiopure 3-methylphthalides

A straightforward synthesis of (S)-3-methylphthalides has been developed, with the key asymmetric step being the bioreduction of 2-acetylbenzonitriles. Enzymatic processes have been found to be highly dependent on the pH value, with acidic conditions being required to avoid undesired side reactions. Baker's yeast was found to be the best biocatalyst acting in a highly stereoselective fashion. The simple treatment of the reaction crudes with aqueous HCl has provided access to enantiopure (S)-3-methylphthalides in moderate to excellent yields.     

Nickel-catalyzed reductive cross-coupling of unactivated alkyl halides

A Ni-catalyzed reductive approach to the cross-coupling of two unactivated alkyl halides has been successfully developed. The reaction works efficiently for primary and secondary halides, with at least one being bromide. The mild reaction conditions allow for excellent functional group tolerance and provide the C(sp(3))-C(sp(3)) coupling products in moderate to excellent yields.     

A cell for high-precision constant-current coulometry with external generation of titrant

A cell has been designed for the high-precision coulometric titration, with externally generated titrant, of materials which otherwise undergo undesirable reactions at the working electrodes. With this cell potassium dichromate has been titrated, via its hydrolysis reaction, with hydroxyl ion generated at the cathode, cathodic reduction of the chromium(VI) being circumvented. In this cell 99.9% of the titrant required is generated in one chamber and transferred to another for reaction; the titration is then completed with titrant generated at a second, drip-type electrode working at much lower current. By means of commercially available Leeds and Northrup coulometric titration electrical equipment, titration of NBS 136b Potassium Dichromate gave a purity of 99.976%, standard deviation 0.005%, and of NBS 84d Potassium Acid Phthalate (done as a check) 99.991%, standard deviation 0.005%, both values being in excellent agreement with other work.     

1－甲氧基－1－锂乙烯的结构及其分解反应的DFT研究

用量子化学中的密度泛函DFT方法，在B3LYP／631G（d,p）水平上研究了－甲 氧基－1－锂乙烯的结构。结果表明，1－甲氧基－1－锂乙烯有4种平衡结构，其中 只有1种是稳定的。对稳定的平衡结构，找到了分解反应的过渡态。在得到分解反 应过渡态的基础上，根据Eyring过渡态理论，计算了不同温度下1-甲氧基－1-钾乙 烯分解反应的速率常数，并根据速率常数计算了其平均寿命τ，根据平均寿命τ讨 论这类物质的稳定性问题。