- Facile Synthesis of a Fully Fused, Three-Dimensional ?-Conjugated Archimedean Cage with Magnetically Shielded Cavity
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The synthesis of molecular cages consisting of fully fused, ?-conjugated rings is rare due to synthetic challenges including preorganization, large strain, and poor solubility. Herein, we report such an example in which a tris-2-aminobenzophenone precursor undergoes acid-mediated self-condensation to form a truncated tetrahedron, one of the 13 Archimedean solids. Formation of eight-membered [1,5]diazocine rings provides preorganization and releases the strain while still maintains weak ?-conjugation of the backbone. Thorough characterizations were performed by X-ray, NMR, and UV-vis analysis, assisted by theoretical calculations. The cage exhibits a rigid backbone structure with a well-defined cavity that confines a magnetically shielded environment. The solvent molecule, o-dichlorobenzene, is precisely encapsulated in the cavity at a 1:1 ratio with multiple ?···?, C-H···?, and halogen···πinteractions with the cage skeleton, implying its template effect for the cage closing reaction. Our synthetic strategy opens the opportunity to access more complex, fully fused, three-dimensional ?-conjugated cages.
- Han, Yi,Jiao, Tianyu,Li, Zhengtao,Ni, Yong,Wu, Jishan,Wu, Shaofei,Zhang, Qiuyu,Zhu, Jun
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supporting information
p. 14314 - 14321
(2021/09/13)
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- Exploiting a silver-bismuth hybrid material as heterogeneous noble metal catalyst for decarboxylations and decarboxylative deuterations of carboxylic acids under batch and continuous flow conditions
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Herein, we report novel catalytic methodologies for protodecarboxylations and decarboxylative deuterations of carboxylic acids utilizing a silver-containing hybrid material as a heterogeneous noble metal catalyst. After an initial batch method development, a chemically intensified continuous flow process was established in a simple packed-bed system which enabled gram-scale protodecarboxlyations without detectable structural degradation of the catalyst. The scope and applicability of the batch and flow processes were demonstrated through decarboxylations of a diverse set of aromatic carboxylic acids. Catalytic decarboxylative deuterations were achieved on the basis of the reaction conditions developed for the protodecarboxylations using D2O as a readily available deuterium source.
- ?tv?s, Sándor B.,Fül?p, Ferenc,Kónya, Zoltán,Kukovecz, ákos,Márton, András,Mészáros, Rebeka,Pálinkó, István,Szabados, Márton,Varga, Gábor
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p. 4685 - 4696
(2021/07/12)
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- Hydrodebromination of Aromatic Bromides Catalyzed by Unsupported Nanoporous Gold: Heterolytic Cleavage of Hydrogen Molecule
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Unsupported nanoporous gold (AuNPore) is a highly efficient, practically applicable, and recyclable catalyst for hydrodebromination of aromatic bromides. The AuNPore-catalyzed hydrodebromination of aromatic bromides proceeded smoothly at relatively low hydrogen pressure and temperature to achieve good to excellent yields of the corresponding non-bromine variants. The selective hydrodebromination reaction occurred exclusively in the coexistence of chlorine atom. For the first time, a mechanistic study revealed that the H?H bond splits in a heterolysis manner on the surface of AuNPore to generate Au?H hydride species.
- Bao, Ming,Feng, Xiujuan,Yamamoto, Yoshinori,Zhang, Sheng,Zhao, Yuhui
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p. 4951 - 4957
(2020/09/09)
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- Direct Stereoselective β-Arylation of Enol Ethers by a Decarboxylative Heck-Type Reaction
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Despite remarkable advances to promote regio- and stereoselective decarboxylative arylation of inactivated olefins with benzoic acid derivatives, methodologies involving hetero-substituted alkenes are still lacking. Herein, PdII-catalyzed decarboxylative Heck coupling of α-alkoxyacrylates with (hetero)aryl carboxylic acids for the stereocontrolled production of (Z)-β-heteroarylated vinyl ethers is reported. This methodology offers a rational and step-economical route to the synthesis of attractive β-arylated α-alkoxy α,β-unsaturated carboxylates family which emerged as a relevant class of building blocks with different applications. Mechanistically, whereas electron rich benzoic acids undergo a PdII-catalyzed decarboxylation, electron-deficient substrates proceed through silver(I)-mediated decarboxylation, explaining thus the formation of stereoisomers (E) and (Z) of β-arylated vinyl ethers in presence of these latter.
- Hachem, Mahmoud,Hoarau, Christophe,Schneider, Cédric
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- Copper-Mediated Fluorination of Aryl Trisiloxanes with Nucleophilic Fluoride
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A method for the nucleophilic fluorination of heptamethyl aryl trisiloxanes to form fluoroarenes is reported. The reaction proceeds in the presence of Cu(OTf)2 and KHF2 as the fluoride source under mild conditions for a broad range of heptamethyltrisiloxyarenes with high functional group tolerance. The combination of this method with the silylation of aryl C?H bonds enables the regioselective fluorination of non-activated arenes controlled by steric effects following a two-step protocol.
- Dorel, Ruth,Boehm, Philip,Schwinger, Daniel P.,Hartwig, John F.
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supporting information
p. 1759 - 1762
(2020/02/05)
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- Controllable synthesis of ultrasmall Pd nanocatalysts templated by supramolecular coordination cages for highly efficient reductive dehalogenation
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Supported ultrasmall noble metal nanocatalysts (UNMNs) are one of the most important classes of solid materials for heterogeneous catalysis. Herein, a simple and efficient supramolecular coordination cage (SCC) template-strategy has been developed to synthesize UNMNs with controllable size and size distribution. A series of SCCs, including M2L4, M4L2, M6L4 and M12L24, with well-defined sizes and shapes as well as different numbers of Pd ions were designed and synthesized as templates. Subsequently, the corresponding Pd nanocatalysts M2&at;CMC, M4&at;CMC, M6&at;CMC and M12&at;CMC were prepared by an impregnation-reduction method on carboxymethylcellulose (CMC) hydrogel supports. It was found that the employment of SCCs as templates could not only significantly reduce the aggregation tendency of Pd nanoparticles but also play an important role in regulating their size and size distribution. For example, the analysis of the catalyst size distribution indicated that the greater the number of Pd ions the cage possesses, the bigger the size of the catalyst. Moreover, with the decrease of the concentration of the template, the size of the Pd nanocatalyst also decreased obviously. Particularly, the resultant catalyst with a nano-Pd loading as high as 12.63percent could still maintain a narrow size distribution. Furthermore, the as-prepared Pd nanocatalyst could serve as a highly efficient polychlorinated biphenyl (PCB) degrader both in a stirred vessel and a continuous flow reactor because of its excellent catalytic efficiency in the reductive dehalogenation reaction under mild conditions. In a word, the SCC template-strategy employed in this study provides new guidelines for the preparation of size-controllable UNMNs on a variety of supports, along with high noble metal loading and catalytic activity. This journal is
- Jiang, Wei-Ling,Peng, Zhiyong,Shen, Ji-Chuang,Shi, Xueliang,Wu, Gui-Yuan,Yang, Hai-Bo,Yin, Guang-Qiang
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supporting information
p. 12097 - 12105
(2020/07/09)
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- Efficient synthesis method of meta-fluoranisole (by machine translation)
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The method is characterized by comprising the following steps: taking m-chloronitrobenzene as a raw material, carrying out high-temperature chlorination reaction, nitration reaction and fluorination reaction to obtain 2,4 - 2,4 -difluorobenzene and carrying out a methoxylation reaction with m-difluorobenzene as a raw material and carrying out methoxylation reaction to obtain m-fluorobenzyl ether; and the hydrogenation catalyst is a porous alumina loaded NiO-Co222O3-MoOO3 composite catalyst. The method disclosed by the invention is simple in process and high in product yield. (by machine translation)
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Paragraph 0026; 0030; 0036; 0040; 0046; 0050; 0056; 0060
(2020/06/05)
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- Synthesis method of m-dichlorobenzene
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The invention relates to a synthesis method of m-dichlorobenzene, which is obtained by translocation reaction with dichlorobenzene as a raw material under the action of a catalyst, wherein the catalyst is an ionic liquid including Lewis acid and onium salt chloride. The synthesis method of the present invention uses an ionic liquid composed of a Lewis acid and an onium salt chloride as a catalyst,the selectivity of the reaction is above 90%, the yield can be significantly increased to above 60%, no under-pressure reaction is required, the reaction conditions are mild, the requirements for equipment are low, the catalyst can be reused many times, the amount of the three wastes is small, the environment is friendly, and the industrial production is suitable.
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Paragraph 0024-0044
(2020/01/03)
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- Chiral fluorescent compound based on cyclophane alkane framework and preparation method and application of compound
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The invention relates to a chiral fluorescent compound based on a cyclophane alkane framework and a preparation method and application of the compound. By using the rigid framework structure of cyclophane alkane, the chirality of the cyclophane alkane can be well kept under the excitation state, and accordingly high asymmetry factors are obtained. By changing R2 and R3 substituent groups, the luminescence section, CPL intensity and luminescence intensity can be regulated and controlled. By changing R1 substituent groups, a thermal-activation delayed fluorescence material is obtained. Phenazinemolecules based on the cyclophane alkane have a good circularly polarized luminescence characteristic and have potential application in the aspects of 3D optical display, information storage and transmission, confidential information recording, optoelectronic devices and even asymmetry photochemical synthesis.
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Paragraph 0061-0080
(2019/11/14)
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- Method for synthesizing dichlorobenzene
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The invention provides a method for synthesizing dichlorobenzene, and the method comprises the following steps: taking trichlorobenzene as a substrate, adding dimethyl sulfoxide (DMSO), an aqueous solution of M(OH)n and a catalyst to form a mixture; stirring and heating the mixture; and contacting hydrogen with the mixture and heating for reaction to obtain the dichlorobenzene; the pH value of theaqueous solution of M(OH)n is great than 7, M is an alkali metal or alkaline earth metal, and n is a positive integer; and the catalyst is a metal catalyst or a metal supported catalyst.
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Paragraph 0061-0080
(2019/11/14)
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- Efficient detoxification of triclosan by a S-Ag/TiO2@g-C3N4 hybrid photocatalyst: Process optimization and bio-toxicity assessment
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Owing to their persistency and toxicity, development of an effective strategy to eliminate antibiotic residues from the aquatic system has become a major environmental concern. Doping TiO2 with hetero atoms and forming a hybrid structure with g-C3N4 could serve as an efficient visible light active photocatalytic candidate. In this study, a novel S-Ag/TiO2@g-C3N4 hybrid catalyst was prepared for visible light degradation and detoxification of triclosan (TS) antibiotic. The effect of various operational parameters towards the photocatalytic degradation was systematically evaluated through response surface methodology (RSM) based on central composite design (CCD). The highest TS degradation (92.3%) was observed under optimal conditions (TS concentration = 10 mg L-1, pH = 7.8, and catalyst weight = 0.20 g L-1) after 60 min. Efficient charge separation resulted from the doped nanoparticles (silver and sulphur), the existing integrated electric field of the heterojunction and the overlying light response of hybridized TiO2 and g-C3N4, thus the S-Ag/TiO2@g-C3N4 composite showed impressively higher activity. The main degradation products of TS were identified by LC/ESI-MS analysis. In addition, the toxicity of the degradation products was investigated through an Escherichia coli (E. coli) colony forming unit assay and the results revealed that under optimal conditions a significant reduction in biotoxicity was noticed.
- Xie, Xiangfeng,Chen, Chen,Wang, Xiaoxiang,Li, Jie,Naraginti, Saraschandra
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p. 20439 - 20449
(2019/07/10)
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- Synthesis method of m-dichlorobenzene
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The invention relates to the technical field of organic synthesis, in particular to a synthesis method of m-dichlorobenzene, and aims to improve the yield and purity of a product. According to the technical scheme, the method comprises the following steps: mixing benzene and concentrated nitric acid, and performing catalytic reaction by taking potassium permanganate as a catalyst to obtain nitrobenzene; mixing nitrobenzene with concentrated nitric acid, and carrying out secondary catalytic reaction to obtain a mixed nitrobenzene solution; mixing and stirring the mixed nitrobenzene, sodium hydrogen sulfite and sodium hydroxide to obtain m-dinitrobenzene; introducing chlorine into m-dinitrobenzene to obtain a crude m-dichlorobenzene solution; carrying out impurity removal treatment on the m-dichlorobenzene solution with a hydrophobic silicalite molecular sieve; crystallizing, rectifying to remove impurities, and carrying out secondary chlorination to obtain pure m-dichlorobenzene; and finally, condensing to obtain a finished product and collecting.
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- Multiphase Hydrodechlorination of 1,3,5-Trichlorobenzene on Palladium Catalysts Supported on Alumina: Effect of the Support Properties and Modification by Heteropoly Acid Based on Silicon and Tungsten
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Abstract: Catalytic systems 2 wt % Pd/Al2O3 were prepared using noncalcined boehmite (NC) and two types of alumina support: one was prepared by the calcination of boehmite at 600°C (C) and the other produced by Engelhard (E). To prepare 2 wt % Pd/HPC–Al2O3 samples, these supports were modified by impregnation by a heteropoly compound (HPC) (20 wt % Н8[Si(W2O7)6] ? 6Н2О). The effect of the Al2O3 structure and its modification by the heteropoly compound on the physicochemical properties, activity, selectivity and stability of catalysts in the reaction of multiphase hydrodechlorination of 1,3,5-trichlorobenzene (TCB) was studied. All catalysts showed activity in the considered reaction with the predominant formation of benzene but were deactivated in the reaction medium. Modification by the heteropoly compound resulted in increased stability and was especially effective for catalyst supported on Al2O3(E). The method of scanning electron microscopy (SEM) was used to determine the morphological differences of supports. According to the data of transmission electron microscopy, all catalysts contained palladium in the form of particles less than 20 nm in size. The particle size and width of the size distribution increases in the series Pd/Al2O3(NC) 2O3(C) 2O3(E). Modification by the heteropoly compound was favorable for the decrease in the size of palladium particles. The method of temperature-programmed reduction with hydrogen (TPR-H2) showed that all catalysts included in their composition palladium hydride along with more strongly surface-bound metal forms that are reduced at elevated temperatures, and their content decreases after modification by the heteropoly compound and increases after catalytic tests. According to diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), the deposition of a heteropoly compound leads to a change in the type of Lewis acid sites on the alumina surface and in the electronic state of palladium. According to the results of infrared spectroscopic studies of adsorbed CO, the relatively large particles of Pd0 are the main form on the surface of nonmodified catalysts. The catalysts modified by the heteropoly compound contain single Pd+ and Pd2+ cations, and the fraction of Pd0 is substantially smaller. The specific features of the Lewis acidity of the catalyst surface determine the possibility of 1,3,5-trichlorobenzene adsorption and activation on the support and the spillover of hydrogen from Pd0. An increase in the catalyst stability as a result of support modification by the heteropoly compound can be explained by the appearance of new active sites in the interaction of palladium with the heteropoly compound or its thermal decomposition products.
- Golubina,Lokteva,Gurbanova,Kharlanov,Egorova,Lipatova,Vlaskin,Shkol’nikov
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p. 297 - 314
(2019/06/24)
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- NITROGEN-CONTAINING BIOPOLYMER-BASED CATALYSTS, THEIR PREPARATION AND USES IN HYDROGENATION PROCESSES, REDUCTIVE DEHALOGENATION AND OXIDATION
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The present invention relates to a process for the preparation of a nitrogen containing biopolymer-based catalyst by pyrolysis of a metal complex with a nitrogen-containing biopolymer and to the nitrogen containing biopolymer-based catalysts obtainable by this process. In particular, the invention relates to a nitrogen containing biopolymer-based catalyst comprising metal particles and at least one nitrogen containing carbon layer. The invention also relates to the use of a nitrogen containing biopolymer-based catalyst in a hydrogenation process, preferably in a process for hydrogenation of nitroarenes, nitriles or imines; in a reductive dehalogenation process of C-X bonds, wherein X is CI, Br or I, preferably in a process for dehalogenation of organohalides or in a process for deuterium labelling of arenes via dehalogenation of organohalides; or in an oxidation process. Further, the invention relates to a metal complex with the nitrogen containing biopolymer, wherein the metal is a transition metal selected from the group consisting of manganese, ruthenium, cobalt, rhodium, nickel, palladium and platinum, preferably cobalt or nickel, and wherein the nitrogen containing biopolymer is selected from chitosan, chitin and a polyamino acid, preferably chitosan or chitin.
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Page/Page column 20-21
(2018/07/29)
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- Selective Hydrogenations and Dechlorinations in Water Mediated by Anionic Surfactant-Stabilized Pd Nanoparticles
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We report a facile, inexpensive, and green method for the preparation of Pd nanoparticles in aqueous medium stabilized by anionic sulfonated surfactants sodium 1-dodecanesulfonate 1a, sodium dodecylbenzenesulfonate 1b, dioctyl sulfosuccinate sodium salt 1c, and poly(ethylene glycol) 4-nonylphenyl-3-sulfopropyl ether potassium salt 1d simply obtained by stirring aqueous solutions of Pd(OAc)2 with the commercial anionic surfactants further treated under hydrogen atmosphere for variable amounts of time. The aqueous Pd nanoparticle solutions were tested in the selective hydrogenation reactions of aryl-alcohols, -aldehydes, and -ketones, leading to complete conversion to the deoxygenated products even in the absence of strong Br?nsted acids in the reduction of aromatic aldehydes and ketones, in the controlled semihydrogenation of alkynes leading to alkenes, and in the efficient hydrodechlorination of aromatic substrates. In all cases, the micellar media were crucial for stabilizing the metal nanoparticles, dissolving substrates, steering product selectivity, and enabling recycling. What is interesting is also that a benchmark catalyst like Pd/C can often be surpassed in activity and/or selectivity in the reactions tested by simply switching to the appropriate commercially available surfactant, thereby providing an easy to use, flexible, and practical catalytic system capable of efficiently addressing a variety of synthetically significant hydrogenation reactions.
- La Sorella, Giorgio,Sperni, Laura,Canton, Patrizia,Coletti, Lisa,Fabris, Fabrizio,Strukul, Giorgio,Scarso, Alessandro
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supporting information
p. 7438 - 7446
(2018/05/29)
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- PROCESS FOR THE PREPARATION OF ORGANIC HALIDES
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The present invention provides a halo-de-carboxylation process for the preparation of organic chlorides, organic bromides and mixtures thereof, from their corresponding carboxylic acids, using a chlorinating agent selected from trichloroisocyanuric acid (TCCA), dichloroisocyanuric acid (DCCA), or combination thereof, and a brominating agent.
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Paragraph 00146
(2017/08/01)
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- Generation of VBr? VBi? VO?? defect clusters for 1O2 production for molecular oxygen activation in photocatalysis
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Defect engineering on a semiconductor surface can provide coordinatively unsaturated sites for molecular oxygen activation in photocatalysis. In this work, we demonstrated that the vacancy type was key to modulate the molecular oxygen activation process on BiOBr nanosheets. By regulating the reaction time, an oxygen vacancy (VO??), a double atom defect cluster (VBi? VO??) and triple atom clusters (VBi? VO?? VBi? and VBr? VBi? VO??) were accordingly generated on the surface, subsurface and bulk of BiOBr. More importantly, the newly-discovered VBr? VBi? VO?? defect cluster was highly related to the singlet oxygen (1O2) production ability of BiOBr. Meanwhile, the excellent photocatalytic selective oxidation reactions were successfully realized over BiOBr with the VBr? VBi? VO?? defect cluster. In addition, time-dependent defect cluster generation and the associated molecular oxygen activation were discussed.
- Ding, Jie,Dai, Zan,Tian, Fan,Zhou, Bo,Zhao, Bin,Zhao, Huiping,Chen, Zhiquan,Liu, Yunling,Chen, Rong
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supporting information
p. 23453 - 23459
(2017/11/30)
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- A Biomass-Derived Non-Noble Cobalt Catalyst for Selective Hydrodehalogenation of Alkyl and (Hetero)Aryl Halides
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Hydrodehalogenation is a straightforward approach for detoxifications of harmful anthropogenic organohalide-based pollutants, as well as removal of halide protecting groups used in multistep syntheses. A novel sustainable catalytic material was prepared from biowaste (chitosan) in combination with an earth-abundant cobalt salt. The heterogeneous catalyst was fully characterized by transmission electron microscope, X-ray diffraction, and X-ray photoelectron spectroscopy measurements, and successfully applied to hydrodehalogenation of alkyl and (hetero)aryl halides with broad scope (>40 examples) and excellent chemoselectivity using molecular hydrogen as a reductant. The general usefulness of this method is demonstrated by successful detoxification of non-degradable pesticides and fire retardants. Moreover, the potential of the catalyst as a deprotection tool is demonstrated in a multistep synthesis of (±)-peronatin B (alkaloid).
- Sahoo, Basudev,Surkus, Annette-Enrica,Pohl, Marga-Martina,Radnik, J?rg,Schneider, Matthias,Bachmann, Stephan,Scalone, Michelangelo,Junge, Kathrin,Beller, Matthias
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supporting information
p. 11242 - 11247
(2017/09/02)
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- M-dichlorobenzene production method
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The invention relates to an m-dichlorobenzene production method. The m-dichlorobenzene production method includes the following steps: mixing benzene with concentrated nitric acid, and performing catalytic reaction by taking the concentrated nitric acid as a catalyst to obtain nitrobenzene; mixing the nitrobenzene with the concentrated nitric acid, and performing secondary catalytic reaction to obtain a mixed nitrobenzene solution; mixing the mixed nitrobenzene solution with sodium hydrogen sulfite and sodium hydroxide, and stirring the mixture to obtain m-dichlorobenzene; injecting chlorine into the m-dichlorobenzene to obtain a coarse m-dichlorobenzene solution; purifying the m-dichlorobenzene solution by hydrophobic silicon zeolite molecular sieves; performing crystallization, rectification, purification and secondary chlorination to obtain pure m-dichlorobenzene; finally condensing the pure m-dichlorobenzene to obtain a finished product, and collecting the finished product. The m-dichlorobenzene production method has the advantages that the benzene is taken as a raw material, the m-dichlorobenzene product with high purity is produced after two times of nitration and repetition of chlorination, the steps of the whole method are simple, requirements on production equipment are low, and the method is suitable for production and application of small and medium enterprises.
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- Thermodynamic Analysis of Isomerization Equilibria of Chlorotoluenes and Dichlorobenzenes in a Biphasic Reaction Systems Containing Highly Acidic Chloroaluminate Melts
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Thermodynamics and kinetics of the isomerization of chlorotoluenes and dichlorobenzene to the technically desired meta-isomers have been studied in the presence of highly acidic chloroaluminate melts with alkali metal and organic imidazolium cations. Enthalpies of four isomerization processes in reacting systems of chlorotoluenes and dichlorobenzene were obtained from temperature dependencies of the corresponding equilibrium constants in the liquid phase. Experimental reaction enthalpies, enthalpies of vaporization, and absolute vapor pressures of chlorotoluenes and dichlorobenzene have been used for the validation of quantum-chemical methods to predict thermodynamic functions of the four reactions under study successfully. Values of the standard Gibbs energies of formation, standard enthalpies and entropies of formation of chlorotoluenes and dichlorobenzenes in the liquid and in the gas phase have been derived. These values allow optimization of liquid-liquid biphasic manufacturing technologies for halogen-substituted benzenes.
- Verevkin, Sergey P.,Messner, Julia,Emel'Yanenko, Vladimir N.,Gantman, Mikhail G.,Schulz, Peter S.,Wasserscheid, Peter
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p. 13152 - 13160
(2017/08/14)
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- Prefunctionalized Porous Organic Polymers: Effective Supports of Surface Palladium Nanoparticles for the Enhancement of Catalytic Performances in Dehalogenation
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Three porous organic polymers (POPs) containing H, COOMe, and COO?groups at 2,6-bis(1,2,3-triazol-4-yl)pyridyl (BTP) units (i.e., POP-1, POP-2, and POP-3, respectively) were prepared for the immobilization of metal nanoparticles (NPs). The ultrafine palladium NPs are uniformly encapsulated in the interior pores of POP-1, whereas uniform- and dual-distributed palladium NPs are located on the external surface of POP-2 and POP-3, respectively. The presence of carboxylate groups not only endows POP-3 an outstanding dispersibility in H2O/EtOH, but also enables the palladium NPs at the surface to show the highest catalytic activity, stability, and recyclability in dehalogenation reactions of chlorobenzene at 25 °C. The palladium NPs on the external surface are effectively stabilized by the functionalized POPs containing BTP units and carboxylate groups, which provides a new insight for highly efficient catalytic systems based on surface metal NPs of porous materials.
- Zhong, Hong,Liu, Caiping,Zhou, Hanghui,Wang, Yangxin,Wang, Ruihu
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p. 12533 - 12541
(2016/08/24)
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- Efficient Route to Deuterated Aromatics by the Deamination of Anilines
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One-step replacement of NH2 groups in ring-substituted anilines by deuterium is reported. Approaches comprising both solid-phase and solution-phase syntheses can be used on a large variety of substrates. The method uses diazotization in a mixture of water and either dichloromethane or chloroform, which serve as a source of hydrogen. This protocol can be used as a general method for fast and easy incorporation of deuterium into an aromatic system using deuterated chloroform.
- Burglova, Kristyna,Okorochenkov, Sergei,Hlavac, Jan
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supporting information
p. 3342 - 3345
(2016/07/26)
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- Radical Hydrodeiodination of Aryl, Alkenyl, Alkynyl, and Alkyl Iodides with an Alcoholate as Organic Chain Reductant through Electron Catalysis
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A simple and efficient method for radical hydrodeiodination is reported. The novel approach uses electron catalysis. In situ generated Na-alcoholates are introduced as radical chain reducing reagents and reactions work with O2as cheap initiator. Hydrodeiodination works on aryl, alkenyl, alkynyl iodides and a tert-alkyl iodide also gets reduced applying the method. Albeit less general, the method is also applicable to the reduction of aryl bromides. The novel reagent is successfully used to conduct typical reductive radical cyclization reactions and mechanistic studies are reported.
- Dewanji, Abhishek,Mück-Lichtenfeld, Christian,Studer, Armido
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supporting information
p. 6749 - 6752
(2016/06/09)
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- Substd. photoisomerization arom. compd. method
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Isomerizing substituted aromatic compounds (I), comprises carrying out isomerization in the presence of a salt melt, which contains a metal compound (II) and at least one metal compound (III). Isomerizing substituted aromatic compounds of formula (Ar1-R n) (I) or their mixtures, comprises carrying out isomerization in the presence of a salt melt, which contains a metal compound of formula ([M1][X1] m 1) (II) and at least one metal compound of formula ([M2][X2] m 2) (III). Ar1 : n-valent aryl radical; R : halo, alkyl, fluoroalkyl, aryl, alkyl-aryl or amino; M1 : Al, Ga, In, Cu, Fe, Co or Ni; X1, X2 : halo, preferably Cl or Br; M2, m2 : alkaline earth metal or alkali metal, where M2 is preferably Li, Na, or K; m1 : Al, Ga, In, Fe(III), Co, Ni or Cu(II); and n : >= 2, preferably 2.
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Paragraph 0062
(2017/01/02)
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- The gold(I)-catalysed protodecarboxylation mechanism
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A mechanistic study of the gold-catalysed protodecarboxylation is described. Each reaction step has been investigated experimentally and computationally. More specifically, the activation parameters for the decarboxylation step have been determined through kinetic studies. Further experimental studies on the hydrolysis of the arylgold intermediate have revealed that the protodeauration can become competitive with the decarboxylation process at high conversions. This switch in rate-limiting step has been shown to be pKa-dependent. These studies have been supported by DFT calculations and permit a better understanding of which prevalent features of the reaction mechanism account for the decarboxylation process.
- Dupuy, St??phanie,Crawford, Luke,B??hl, Michael,Nolan, Steven P.
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supporting information
p. 3399 - 3408
(2015/03/05)
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- Isomerisation of 1,4-dichlorobenzene using highly acidic alkali chloroaluminate melts
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The isomerisation reaction of 1,4-dichlorobenzene leading to the thermodynamically favoured and technically desired 1,3-dichlorobenzene has been studied comparing highly acidic chloroaluminate melts with organic imidazolium and alkali metal ions. Interestingly, the inorganic melts show much higher reactivity and full recyclability if small AlCl3 losses are compensated and the reaction is carried out under slight HCl pressure. This journal is
- Messner,Schulz,Taccardi,Kuhlmann, Sven,Wasserscheid
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p. 11705 - 11708
(2015/05/20)
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- Base-promoted protodeboronation of 2,6-disubstituted arylboronic acids
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Facile based promoted deboronation of electron-deficient arylboronate esters was observed for arylboronates containing two ortho electron-withdrawing group (EWG) substituents. Among 30 representative boronates, only the diortho-substituted species underwe
- Lozada, Jerome,Liu, Zhibo,Perrin, David M.
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supporting information
p. 5365 - 5368
(2014/06/23)
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- Iron(III)-mediated photocatalytic selective substitution of aryl bromine by chlorine with high chloride utilization efficiency
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An iron(III)-mediated photocatalytic method for the conversion of aryl, heteroaryl and polycyclic aromatic bromides to the corresponding chlorides with high selectivity has been achieved successfully. The mild reaction conditions and high chloride utilization efficiency promise a bright future for chlorination reactions. The Royal Society of Chemistry 2014.
- Wang, Ying,Li, Lina,Ji, Hongwei,Ma, Wanhong,Chen, Chuncheng,Zhao, Jincai
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supporting information
p. 2344 - 2346
(2014/03/21)
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- Gold(I)-catalyzed protodecarboxylation of (Hetero)aromatic carboxylic acids
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Readily available, inexpensive and easy to handle, carboxylic acids have been shown to be very effective, greener coupling partners compared to costly organometallic reagents for the formation of C-C bonds. The use of well-defined gold complexes furnished 3 in slightly better yield with butyric acid, and in quantitative yield with adamantane-1-carboxylic acid. All reactions reached completion within 16 h. As with silver systems, this reactivity trend highlights, as previously observed, the benefits of potential coordinating groups in the ortho position to the gold binding site, which possibly facilitate the decarboxylation step. Additional reaction time and increased temperatures were necessary to afford the gold aryl products in satisfactory yields. Yet, some substrates such as 2-nitrobenzoic acids reacted poorly and could only be transformed in 50% yield.
- Dupuy, Stéphanie,Nolan, Steven P.
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supporting information
p. 14034 - 14038
(2013/11/19)
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- Cu(I)/cu(II)/TMEDA, new effective available catalyst of sandmeyer reaction
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The system Cu(I)/Cu(II)/N,N,N',N'-tetramethylethylenediamine is a highly effi cient and accessible catalyst of Sandmeyer reaction. The reaction of aryldiazonium salts with chlorides, bromides cyanides, and thiocyanates of alkaline metals in the presence of this catalytic system leads to the formation of the corresponding aryl halides, nitriles, and thiocyanates in high yields.
- Sigeev, A. S.,Beletskaya, I. P.,Petrovskii, P. V.,Peregudov, A. S.
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p. 1055 - 1058,4
(2020/10/15)
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- Water-soluble complexes MX2L2 (M = Pd, Pt; L = PPh2(C6H4-p-SO3K)): Synthesis, stereoisomerism, and catalytic activities for aromatic cyanation in n-heptane/water biphasic solution
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Reaction of (COD)MX2 (M = Pd, Pt; X = Cl, I; COD = 1,5-cyclooctadiene) and P(C6H5)2(C 6H4-p-SO3K) afforded water-soluble complexes MX2{P(C6H5)2(C6H 4-p-SO3K)}2 (M = Pd; X = Cl (1), M = Pt; X = Cl (2), I (3)) in high yields. Complexes 1-3 were fully characterized by various spectroscopic methods (IR, 1H-, 13C{1H}- and 31P{1H}-NMR spectroscopy) and elemental analyses. For 1 and 3, a mixture of the cis- and trans-isomer was produced from the reaction. For 2, however, only the cis-isomer was obtained. The stereochemistry of 1-3 can be assigned by the chemical shifts and the 1J(Pt-P) values in 31P{1H}-NMR spectral data. The ratios of the cis/trans isomers of 1 and 3 obtained from reactions in a range of solvents with various dielectric constants resulted in a little variation. However, addition of aqueous potassium halide solution to a DMSO-d6 solution of 1 and 3 considerably increased the ratio of the cis/trans, respectively, indicating a strong intramolecular interligand Coulombic repulsion between the ionic phosphine ligands is present. Catalytic cyanation of aromatic iodide with KCN/ZnCl2 in n-heptane/water biphasic system has been tested in the presence of 1-3 with base.
- Shim, Young Ji,Lee, Ho Jin,Park, Soonheum
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experimental part
p. 4173 - 4178
(2012/01/13)
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- Exceptionally high decarboxylation rate of a primary aliphatic acyloxy radical determined by radical product yield analysis and quantitative 1H-CIDNP spectroscopy
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Symmetrical (RCO2CO2R; R=XCH2CH 2) and asymmetrical (RCO2CO2R′; R=C 9H19CH2CH2, R′=CH3 or m-ClC6H4) primary diacyl peroxides were thermally decomposed under different conditions to analyze the decarboxylation rates of the thermally generated acyloxy radicals. Quantitative models of the geminate product yields, and qualitative and quantitative 1H-CIDNP spectroscopy were used to obtain the decarboxylation rate estimates. Results reported here suggest that, unlike short chain acyloxy radicals such as propanoyloxyl, long chain acyloxy radicals possess the highest decarboxylation rates of all known acyloxy radicals, estimated at (0.5-1.5)× 10 12s-1 between 80 and 140°C. Given the nature of the dissociative state of acyloxy radicals, such rates appear to be the result of destabilization of the former by the steric bulk of the long chain substituents. Additionally, the rate of this order of magnitude suggests a nearly concerted decarboxylation of primary diacyl peroxides. Copyright
- Fraind, Alicia,Turncliff, Ryan,Fox, Teri,Sodano, Justin,Ryzhkov, Lev R.
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scheme or table
p. 809 - 820
(2012/06/29)
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- Cobalt-catalyzed preparation of arylindium reagents from aryl and heteroaryl bromides
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A cobalt-bathophenanthroline catalyst has been developed for the direct preparation of a variety of arylindium reagents from the corresponding aryl and heteroaryl bromides in the presence of indium metal and lithium chloride. The thus-formed arylindium reagents undergo efficient palladium-catalyzed cross-coupling reactions with aryl iodides, tolerating various functional groups including hydroxy and free amino groups.
- Adak, Laksmikanta,Yoshikai, Naohiko
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experimental part
p. 7563 - 7568
(2011/11/12)
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- Kinetic study of the hydrogenolysis of polychlorobenzenes over a Pd/C catalyst in an alkaline aqueous-n-hexane system
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The kinetics of the hydrogenolysis of chlorobenzene, dichlorobenzenes and some trichlorobenzenes over a 10% Pd/C catalyst was studied using a multiphase system. The reactions were carried out in a batch reactor with an aqueous NaOH/n-hexane solution of chloroaromatic compound as the liquid phase. Benzene was the final product of the hydrogenolysis of all the compounds studied. Hydrogenolysis was more effective in the presence of in situ generated hydrogen than gaseous hydrogen. The initial reaction rates and TOFs of dichlorobenzenes and trichlorobenzenes were slightly lower than those of chlorobenzene. The position of the chlorine atoms in trichlorobenzenes affects the kinetics of the removal of the first chlorine from these molecules. The differences in chlorine reactivity were explained by the inductive and steric effects induced by the benzene-Cl bonds.
- Anusiewicz, Iwona,Janiak, Tadeusz,Okal, Janina
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experimental part
p. 797 - 801
(2010/07/06)
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- Silver-catalysed protodecarboxylation of carboxylic acids
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A silver-based catalyst system has been discovered that effectively promotes the protodecarboxylation of various carboxylic acids at temperatures of 80-120 °C - more than 50 °C below those of the best known copper catalysts. The Royal Society of Chemistry 2009.
- Goossen, Lukas J.,Linder, Christophe,Rodriguez, Nuria,Lange, Paul P.,Fromm, Andreas
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supporting information; experimental part
p. 7173 - 7175
(2010/03/25)
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- Silver-catalysed protodecarboxylation of ortho-substituted benzoic acids
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Catalytic amounts of Ag(i) salts in DMSO have been found to promote the protodecarboxylation of a wide variety of ortho-substituted benzoic acids under mild conditions and in excellent yields, highlighting a possible role for silver in decarboxylative cross-couplings. The Royal Society of Chemistry 2009.
- Cornella, Josep,Sanchez, Carolina,Banawa, David,Larrosa, Igor
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supporting information; experimental part
p. 7176 - 7178
(2010/03/25)
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- CAN-mediated oxidation of electron-deficient aryl and heteroaryl hydrazines and hydrazides
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Aryl and heteroaryl hydrazines and hydrazides were successfully oxidised using CAN, deriving dehydrazinated products. The reaction pathway strongly depends on the nature of the substrate, resulting in the formation of hydrocarbons or alkoxy derivatives. When deuterated solvents such as methanol-d4 or acetonitrile-d3 were used, a regiospecific incorporation of deuterium was achieved. Georg Thieme Verlag Stuttgart.
- ?tefane, Bogdan,Polanc, Slovenko
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scheme or table
p. 1279 - 1282
(2009/04/06)
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- Palladium on ultradisperse diamond and activated carbon: The relation between structure and activity in hydrodechlorination
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Ultradisperse diamond was studied as a promising carrier for Pd-containing hydrodechlorination catalysts. Transmission electron microscopy, temperature-programmed reduction, and the adsorption method were used to study catalysts on ultradisperse diamond and activated carbon and a commercial catalyst from Fluca. Catalyst activities in multiphase hydrodechlorination of chlorobenzenes were compared. The activity of Pd-containing catalysts on ultradisperse diamond was found to be several orders of magnitude higher than that of Pd catalysts on activated carbon. Nauka/Interperiodica 2007.
- Kachevskii,Golubina,Lokteva,Lunin
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p. 866 - 873
(2008/02/12)
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- Method for separating substances
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An objective of the present invention is to provide electrophoretic separation methods and devices that enable the various features of a substrate surface that comes in contact with an electrophoresis medium to be controlled. The present invention provides methods for electrophoresing substances, which comprises the steps of: (a) adding a substance to be analyzed to an electrophoresis medium retained in a substrate, whose surface that has come in contact with the electrophoresis medium has been coated with a polymer membrane; and (b) adding electrophoretic pressure to the electrophoresis medium. For example, the use of a plasma-polymerized membrane allows the formation of a membrane with homogeneous quality and thickness on the surface of an arbitrary shape. In addition, desired characteristics can be conferred on the surface through selection of monomeric substances. Protein adsorption onto micro-chips can be effectively prevented as well.
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- METHOD FOR PRODUCING P-DICHLOROBENZENE
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In a process for preparing p-dichlorobenzene by nuclear chlorination of benzene and/or chlorobenzene as the starting material with chlorine molecules, chlorination is carried out using aluminum chloride in an amount of 0.1 - 3 millimols per mol of the starting material and phenothiazines such as 10H-phenothiazine-10-carboxylic acid phenyl ester in an amount of 0.1 - 0.9 mols per mol of aluminum chloride so as to be a chlorination degree in a range of 1.2 - 2.5, by which p-dichlorobenzene can be obtained in a high para-selectivity and a short reaction time.
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Page/Page column 5
(2008/06/13)
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- PROCESS FOR HALOGENATION OF BENZENE AND BENZENE DERIVATIVES
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In a process of halogenation of benzene or benzene derivatives, di-substituted halobenzene derivatives having para-aromatic compounds or tri-substituted halobenzene derivatives having 1,2,4-substituted aromatic compounds are selectively produced. In halogenation of benzene or benzene derivatives, a fluorine-containing zeolite catalyst such as L-type zeolite, or a zeolite catalyst having the crystal size of at most 100 nm is used. The reaction is preferably effected in the presence of a solvent, and the solvent is preferably a halogenated compound.
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Page/Page column 20; 21
(2008/06/13)
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- PROCESS FOR HYDRODEHALOGENATION OF AROMATIC POLYHALIDES WITH ISOPROPYL ALCOHOL AS THE HYDROGEN SOURCE
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A method for dehalogenative hydrogenation for aromatic polyhalogenated compounds comprising, making progress the dehalogenative hydrogenation reaction of said aromatic polyhalogenated compounds, under the presence of aromatic polyhalogenated compounds, inorganic basic aqueous solution as a scavenger of halogenated hydrogen generated by the dehalogenative hydrogenation of said aromatic polyhalogenated compounds, isopropylalcohol as a hydrogen supplying agent at the dehalogenative hydrogenation reaction and catalysts which catalyzes the dehalogenative hydrogenation reaction of said aromatic polyhalogenated compounds consisting of at least organic nickel complex and PPh3.
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- Process for the separation of mixtures containing m- and p-dichlorobenzene
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Phosphate esters (I) and phosphine oxides (II) are used as extractants for extractive distillation. Phosphate esters of formula (I) and phosphine oxides of formula (II) are used as extractants for extractive distillation. R = (cyclo)alkyl or (cyclo)alkenyl groups containing a total of 3-12 C atoms; and R' = H or (cyclo)alkyl or (cyclo)alkenyl groups containing a total of 3-12 C atoms. An Independent claim is also included for separation of m- and p-dichlorobenzene by extractive distillation using a phosphate ester (I) and/or a phosphine oxide (II) as the extractant:
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Page column 7
(2008/06/13)
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- Formation and destruction of chlorinated pollutants during sewage sludge incineration
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The limitations facing land filling and recycling and the planned ban on sea disposal of sludge leads to the expectation that the role of sludge incineration will increase in the future. The expected increase in sludge incineration will also increase scrutiny of the main drawback to sewage sludge incineration-the formation of hazardous air pollutants (HAPs). Despite the extensive body of knowledge available on sewage sludge combustion, very few studies have been conducted on the formation of HAPs during sludge combustion. In this work, the interactions between sewage sludge pyrolysis products and sludge ash were investigated using a dual chamber flow reactor system and a horizontal laboratory scale reactor. The results of this study shows that sludge ash can catalyze oxidation and chlorination of organics. In the absence of HCl in the gas stream, sludge ash acts as an oxidizing catalyst, but in the presence of HCl, sludge ash acts as a chlorination catalyst producing high yields of organochloride compounds.
- Fullana, Andres,Conesa, Juan A.,Font, Rafael,Sidhu, Sukh
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p. 2953 - 2958
(2007/10/03)
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- Electroreduction of polychlorobenzenes using either lead or copper electrodes
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Polychlorobenzenes can be reduced electrolytically to dichlorobenzenes by using either lead or copper as the electrodes in a MeOH/THF solution. Among the resultants of dichlorobenzenes, 1,4-dichlorobenzene is a major product that might be due to a low enthalpy of formation. A chlorine atom situated at the ortho position of another chlorine atom in the benzene ring is removed prior to others. However, the sequence of reactivities of the polychlorobenzenes for electroreducing by lead electrodes in this study is as follows: 1,2,3,4-C 6H2Cl4 > 1,3,5-C6H 3Cl3 > C6HCl5 - 1,2,4,5-C 6H2Cl4 > 1,2,3,5-C6H 2Cl4 - 1,2,3-C6H3Cl3 > 1,2,4-C6H3Cl3 > C6Cl 6.
- Lin, Shaw-Tao,Chao, Richard Yung-Ho,Lin, Sun-Che,Lin, Shu-Fan
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p. 539 - 544
(2007/10/03)
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- A new advanced method for heterogeneous catalysed dechlorination of 1,2,3-, 1,2,4-, and 1,3,5-trichlorobenzenes in hydrocarbon solvent
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A new advanced method for dechlorination of 1,2,3-, 1,2,4-, and 1,3,5-trichlorobenzenes in organic solvent catalysed by palladium on carbon support and solid hydrazine hydrochloride yields benzene in short reaction times. The catalyst system can be efficiently reused for several cycles. Ultrasound radiation of the heterogeneous catalyst reaction increases remarkably the rate of dechlorination.
- Rodríguez, J. Gonzalo,Lafuente, Antonio
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p. 9645 - 9647
(2007/10/03)
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- 1-Aryl-3,3-dialkyltriazenes: A convenient synthesis from dry arenediazonium o-benzenedisulfonimides - A high yield break down to the starting dry salts and efficient conversions to aryl iodides, bromides and chlorides
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This research comprises three parts. The first part regards the synthesis of 1-aryl-3,3-dialkyltriazenes 3 by reaction of dry arenediazonium o-benzenedisulfonimides 1, also coming from weakly basic aromatic amines with dimethylamine or diethylamine in aqueous solution at 0-5 °C. Yields were usually greater than 90% and there was the possibility of recovering the o-benzenedisulfonimide (5), which could be reused to prepare the salts 1. In the second part it was demonstrated that there is the possibility of reconverting the triazenes 3 into the starting stable dry salts 1 by using 5 as acid. The reactions were carried out in glacial acetic acid at 50-55 °C and normally afforded salts 1 in yields of around 90-99%. The third part concerns the setting up of two procedures for the conversion of 3 to aryl iodides 9, bromides 10 and chlorides 11. Procedure A used the corresponding aqueous hydrogen halides in acetonitrile at r.t. or 60 °C, sometimes in the presence of aqueous HBF4, sometimes Cu powder (25 examples, yields 65%-88%). Procedure B usually used anhydrous methanesulfonic acid and tetraalkylammonium halides in anhydrous acetonitrile at temperatures varying from r.t. to 80 °C, sometimes in the presence of Cu (16 examples, yields 65-88%).
- Barbero,Degani,Diulgheroff,Dughera,Fochi
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p. 2180 - 2190
(2007/10/03)
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- Reactions of 2,4,6-trichlorophenol on model fly ash: Oxidation to CO and CO2, condensation to PCDD/F and conversion into related compounds
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Thermal treatment of 2,4,6-trichlorophenol on a magnesium silicate-based model fly ash in the temperature range between 250°C and 400°C leads predominantly to carbon monoxide and carbon dioxide. The fraction of 2,4,6-trichlorophenol which is oxidized to CO and CO2 increases from 3% at 250°C to 75% at 400°C. Further products are polychlorinated benzenes, dibenzo-p-dioxins, dibenzofurans and phenols. The homologue and isomer patterns of the chlorobenzenes suggest chlorination in the ipso-position of the trichlorophenol. The formation of PCDD from 2,4,6-trichlorophenol and 2,3,4,6-tetrachlorophenol on municipal solid waste incinerator fly ashes and model fly ash were compared and the reaction order calculated.
- Hell,Stieglitz,Altwicker,Addink,Will
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p. 697 - 702
(2007/10/03)
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- Formation and decomposition of chloroaromatic compounds in chlorine-containing benzene/oxygen flames
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Premixed chlorine-containing, fuel-rich, low-pressure benzene/oxygen flames were analysed for the formation of (oxygenated) chloroaromatic compounds and their radicals by means of the condensation/radical-scavenging method (Hausmann, M., Homann, K.-H., 1995. Ber. Busenges. Phys. Chem. 99, 853-862). Several chlorinated organic compounds (methyl chloride, t-butyl chloride, chlorobenzene, chloroform) were used as additives within a maximum concentration of 10% of total fuel. Product identification and quantification were performed by GC/MS. The extent of formation of chloroaromatic compounds in these flames was largest in the cases of chlorobenzene and chloroform as additives. For chlorobenzene, 12 different chloroaromatics could be analysed in between C7H7Cl and C12H9Cl. Their formation is mainly due to conversion of initial chlorobenzene into substituted or oxidised derivatives, or growth products. Additional chlorination of aromatics is shown to be of minor importance in chlorobenzene-containing flames. Three isomeric (o/m/p) scavenging products could be identified for the chlorophenyl radical. In the chloroform case, 15 chloroaromatics could be analysed in between C6H5Cl and C14H9Cl. The weak C-Cl bond in chloroform is responsible for the high extent of chloroaromatics formation, either by Cl abstraction from the additive or by chlorination reactions via Cl radicals. Additionally, specific pathways to (di)chloroaromatics and chlorinated fulvene-type structures are outlined via CHCl2 and CCl2 radicals.
- Burfeindt,Homann
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p. 439 - 447
(2007/10/03)
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- Identification of surrogate compounds for the emission of PCDD/F (I-TEQ value) and evaluation of their on-line realtime detectability in flue gases of waste incineration plants by REMPI-TOFMS mass spectrometry
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Correlations between products of incomplete combustion (PIC), e.g., chloroaromatic compounds, can be used to characterise the emissions from combustion processes, like municipal or hazardous waste incineration. A possible application of such relationships may be the on-line real-time monitoring of a characteristic surrogate, e.g., with Resonance-Enhanced Multiphoton Ionization-Time-of-Flight Mass Spectrometry (REMPI-TOFMS). In this paper, we report the relationships of homologues and individual congeners of chlorinated benzenes (PCBz), dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF) and phenols (PCPh) to the International Toxicity Equivalent (I-TEQ) of the PCDD/F (I-TEQ value) in the flue gas and stack gas of a 22 MW hazardous waste incinerator (HWI). As the REMPI detection sensitivity is decreasing with the increase of the degree of chlorination, this study focuses on the lower chlorinated species of the compounds mentioned above. Lower chlorinated species, e.g., chlorobenzene (MCBz), 1,4-dichlorobenzene, 2,4,6-trichlorodibenzofuran or 2,4-dichlorophenol, were identified as I-TEQ surrogates in the flue gas. In contrast to the higher chlorinated phenols, the lower chlorinated phenols (degree of chlorination 4) were not reliable as surrogates in the stack gas. The identified surrogates are evaluated in terms of their detectability by REMPI-TOFMS laser mass spectrometry. The outcome is that MCBz is the best suited surrogate for (indirect) on-line measuring of the I-TEQ value in the flue gas by REMPI-TOFMS. The correlation coefficient r of the MCBz concentration to the I-TEQ in the flue gas was 0.85.
- Blumenstock,Zimmermann,Schramm,Kettrup
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p. 507 - 518
(2007/10/03)
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