- Selective electrochemical oxidation of aromatic hydrocarbons and preparation of mono/multi-carbonyl compounds
-
A selective electrochemical oxidation was developed under mild condition. Various mono-carbonyl and multi-carbonyl compounds can be prepared from different aromatic hydrocarbons with moderate to excellent yield and selectivity by virtue of this electrochemical oxidation. The produced carbonyl compounds can be further transformed into α-ketoamides, homoallylic alcohols and oximes in a one-pot reaction. In particular, a series of α-ketoamides were prepared in a one-pot continuous electrolysis. Mechanistic studies showed that 2,2,2-trifluoroethan-1-ol (TFE) can interact with catalyst species and generate the corresponding hydrogen-bonding complex to enhance the electrochemical oxidation performance. [Figure not available: see fulltext.]
- Li, Zhibin,Zhang, Yan,Li, Kuiliang,Zhou, Zhenghong,Zha, Zhenggen,Wang, Zhiyong
-
p. 2134 - 2141
(2021/09/29)
-
- Visible-Light-Driven Selective Air-Oxygenation of C?H Bond via CeCl3 Catalysis in Water
-
Visible-light-induced C?H aerobic oxidation is an important chemical transformation that can be applied for the synthesis of aromatic ketones. High-cost catalysts and toxic solvents were generally needed in the present methodologies. Here, an efficient aqueous C?H aerobic oxidation protocol was reported. Through CeCl3-mediated photocatalysis, a series of aromatic ketones were produced in moderate to excellent yields. With air as the oxidant, this reaction could be performed under mild conditions in water and demonstrated high activity and functional group tolerance. This method is economical, highly efficient, and environmentally friendly, and it will provide inspiration for the development of aqueous photochemical synthesis reactions.
- Xie, Pan,Xue, Cheng,Shi, Sanshan,Du, Dongdong
-
p. 2689 - 2693
(2021/05/07)
-
- Decatungstate-mediated solar photooxidative cleavage of CC bonds using air as an oxidant in water
-
With the increasing attention for green chemistry and sustainable development, there has been much interest in searching for greener methods and sources in organic synthesis. However, toxic additives or solvents are inevitably involved in most organic transformations. Herein, we first report the combination of direct utilization of solar energy, air as the oxidant and water as the solvent for the selective cleavage of CC double bonds in aryl olefins. Various α-methyl styrenes, diaryl alkenes as well as terminal styrenes are well tolerated in this green and sustainable strategy and furnished the desired carbonyl products in satisfactory yields. Like heterogeneous catalysis, this homogeneous catalytic system could also be reused and it retains good activity even after repeating three times. Mechanism investigations indicated that both O2- and 1O2 were involved in the reaction. Based on these results, two possible mechanisms, including the electron transfer pathway and the energy transfer pathway, were proposed.
- Du, Dongdong,Luo, Junfei,Shi, Sanshan,Xie, Pan,Xue, Cheng
-
p. 5936 - 5943
(2021/08/23)
-
- Photoinduced Iron-Catalyzed ipso-Nitration of Aryl Halides via Single-Electron Transfer
-
A photoinduced iron-catalyzed ipso-nitration of aryl halides with KNO2 has been developed, in which aryl iodides, bromides, and some of aryl chlorides are feasible. The mechanism investigations show that the in situ formed iron complex by FeSO4, KNO2, and 1,10-phenanthroline acts as the light-harvesting photocatalyst with a longer lifetime of the excited state, and the reaction undergoes a photoinduced single-electron transfer (SET) process. This work represents an example for the photoinduced iron-catalyzed Ullmann-type couplings.
- Wu, Cunluo,Bian, Qilong,Ding, Tao,Tang, Mingming,Zhang, Wenkai,Xu, Yuanqing,Liu, Baoying,Xu, Hao,Li, Hai-Bei,Fu, Hua
-
p. 9561 - 9568
(2021/08/06)
-
- Iron-catalyzed domino decarboxylation-oxidation of α,β-unsaturated carboxylic acids enabled aldehyde C-H methylation
-
A practical and general iron-catalyzed domino decarboxylation-oxidation of α,β-unsaturated carboxylic acids enabling aldehyde C-H methylation for the synthesis of methyl ketones has been developed. This mild, operationally simple method uses ambient air as the sole oxidant and tolerates sensitive functional groups for the late-stage functionalization of complex natural-product-derived and polyfunctionalized molecules.
- Gong, Pei-Xue,Xu, Fangning,Cheng, Lu,Gong, Xu,Zhang, Jie,Gu, Wei-Jin,Han, Wei
-
supporting information
p. 5905 - 5908
(2021/06/18)
-
- Interfacially synthesized 2D COF thin film photocatalyst: efficient photocatalyst for solar formic acid production from CO2and fine chemical synthesis
-
The targeted synthesis of an efficient, visible light active, recyclable, freestanding covalent organic framework thin film photocatalyst for multi-faceted photocatalysis is the essence of the proposed work. A simple, scalable, reagent free synthesis of a thin film at the interface of 5,10,15,20-tetra-(4-aminophenyl)porphyrin, 2-vinylbenzene-1,4-dicarbaldehyde in nitrobenzene and aqueous glyoxal affords centimetre sized continuous 2D thin film with substantial stability, flexibility and efficient visible light activity. Strikingly different from the regular imine based COF, the incorporation of the glyoxal unit as a modulator helps in band gap tuning and induces flexibility within the thin film. An interplay between time and concentration helps in achieving a thin film photocatalyst with efficient photocatalytic activity for 1,4-NADH regeneration and selective formic acid formation from CO2. The optimum band edge position of the thin film photocatalyst also enables solar fine chemical synthesisviareductive dehalogenation under visible light illumination with excellent recyclability. The present work gives insight into visible light active thin film formation en route to metal-free sustainable photocatalysis.
- Yadav, Dolly,Kumar, Abhishek,Kim, Jae Young,Park, No-Joong,Baeg, Jin-Ook
-
supporting information
p. 9573 - 9580
(2021/04/26)
-
- Preparation method of O-aminoacetophenone
-
The invention relates to the technical field of organic intermediate synthesis, in particular to a preparation method of o-aminoacetophenone. The preparation method of o-aminoacetophenone provided bythe invention comprises the following steps: adding potassium permanganate into o-nitroethylbenzene in batches in an acidic environment of dilute sulfuric acid to carry out oxidation reaction to generate o-nitroacetophenone; reducing the o-nitroacetophenone into o-aminoacetophenone by using iron powder; and distilling off o-aminoacetophenone by using water vapor. The reaction conditions are mild,the production cost is low, the method is suitable for industrial mass production, the yield of the o-nitroacetophenone can reach 70% or above, the yield of the o-aminoacetophenone can reach 90% or above, and the yield of the o-nitroacetophenone and the yield of the o-aminoacetophenone can both reach 95% or above when weak acid glacial acetic acid is adopted as a catalyst and all the raw materialsare kept in the optimal proportion and react under the optimal reaction condition.
- -
-
Paragraph 0037-0038; 0040-0041; 0043-0044; 0046-0047; 0049
(2020/09/30)
-
- Visible-light assisted of nano Ni/g-C3N4 with efficient photocatalytic activity and stability for selective aerobic C?H activation and epoxidation
-
A selective, economical, and ecological protocol has been described for the oxidation of methyl arenes and their analogs to the corresponding carbonyl compounds and epoxidation reactions of alkenes with molecular oxygen (O2) or air as a green oxygen source, under mild reaction conditions. The nano Ni/g-C3N4 exhibited high photocatalytic activity, stability, and selectivity in the C?H activation of methyl arenes, methylene arenes, and epoxidation of various alkenes under visible- light irradiation without the use of an oxidizing agent and under base free conditions.
- Akrami, Zahra,Hosseini-Sarvari, Mona
-
supporting information
(2020/10/13)
-
- Preparation method of O-aminoacetophenone
-
The invention discloses a preparation method of o-aminoacetophenone. The preparation method comprises the following steps: (1) mixing o-nitroethylbenzene, an oxidant, a cocatalyst and an organic solvent, heating the obtained mixed solution to a certain temperature for a reaction, and subjecting the reacted solution to cooling, quenching and extracting to obtain o-nitroacetophenone; and (2) addinga polar solvent and a metal catalyst into the obtained o-nitroacetophenone, carrying out a hydrogenation reduction reaction to obtain a crude o-aminoacetophenone product, and filtering and rectifyingthe crude o-aminoacetophenone product to obtain a refined o-aminoacetophenone product. According to the invention, used raw materials are low in price and easy to obtain, and steps are simple and easyto operate. The o-aminoacetophenone obtained by the method disclosed by the invention is high in purity and high in yield.
- -
-
Paragraph 0047; 0048; 0050; 0051; 0053; 0054; 0056; 0057
(2020/04/17)
-
- Visible-light-driven photochemical activity of ternary Ag/AgBr/TiO2nanotubes for oxidation C(sp3)-H and C(sp2)-H bonds
-
The Ag/AgBr/TiO2 ternary component nanotube as a heterogeneous photocatalyst was used for the solvent-free oxidation of the benzylic C(sp3)-H bond to the corresponding carbonyl compound or the solvent-controlled selective oxidative cleavage of the CC double bond of styrene to benzaldehyde under visible light at room temperature. A wide variety of carbonyl compounds were successfully synthesized through the developed photocatalytic process. Several advantages such as solvent-free conditions, sans additional oxidant, simple reaction, short reaction time, and easy separation of the product promote the reaction to be green. Moreover, the Ag/AgBr/TiO2 nanotubes could be used several times without reduction in their photocatalytic activity. This journal is
- Hosseini-Sarvari, Mona,Dehghani, Abdulhamid
-
p. 16776 - 16785
(2020/10/27)
-
- Highly Active and Robust Ruthenium Complexes Based on Hemilability of Hybrid Ligands for C-H Oxidation
-
Evaluation of the hemilability of hybrid ligands provides a key to understand the metal-ligand cooperation in transition metal catalysis. Here, we design and synthesize a type of RuII complexes based on the hemilability of N-heterocyclic carbenes (NHCs), pyridine, and pyrazole, to compare their activity with other reported Ru catalysts in benzylic C-H oxidation. The RuII catalysts showed ultrastrong catalytic activity in water at room temperature and achieved a turnover frequency (TOF) of 114 h-1, which is the highest TOF value ever reported for Ru-catalyzed benzylic C-H oxidation. The addition of tridentate hybrid ligands in the Ru central position has two beneficial effects: NHCs with a stronger donor ability stabilize the Ru center; however, nitrogen ligands with a relatively weaker donor ability release from the Ru center, so that they induce a reaction. UV-vis, high-resolution electrospray ionization mass spectrometry (ESI-MS), electron paramagnetic resonance (EPR) spectrometry, the trapping of radicals, and the density functional theory calculations (DFT) suggested that a cation catalyst L-RuII-tBuO2H is formed via the reaction between starting RuII catalysts and tert-butyl hydroperoxide, which further undergoes a cleavage of the O-O bond to generate a radical and a cation L-RuIII-OH active intermediate.
- Bo, Chun-Bo,Bu, Qingqing,Li, Xue,Ma, Ge,Wei, Donghui,Guo, Cheng,Dai, Bin,Liu, Ning
-
p. 4324 - 4334
(2020/03/05)
-
- Method for synthesizing O-aminoacetophenone (by machine translation)
-
The invention discloses a method for synthesizing a medical intermediate o-aminoacetophenone, wherein o-ethyl nitrobenzene is taken as a starting raw material, and the compound is obtained by reacting an ethyl oxide with a reducing nitro 2 step. To the synthesis method, o-aminoacetophenone is synthesized, a novel oxidizing agent and a reducing agent are adopted, the yield 56% is around, and the method has the characteristics of high process safety, low material price, easiness in production and amplification and the like. (by machine translation)
- -
-
Paragraph 0038-0043; 0057-0061
(2020/09/20)
-
- Visible-Light-Driven Direct Oxidative Coupling Reaction Leading to Alkyl Aryl Ketones, Catalyzed by Nano Pd/ZnO
-
Direct alkyl sp3 C–H activation to form new C–C bonds is one of the major challenges in synthetic chemistry. Herein, for the first time, we represent a new method, using nano Pd/ZnO which plays both as photoredox and transition-metal catalyst, for C–C bond formations. By using this catalyst, we have accomplished an oxidative coupling reaction between aryl halides and tertiary amines to yield the corresponding naturally occurring alkyl aryl ketones by using visible light irradiation. Furthermore, the carbonylation process was carried out on a 10 gram scale, with visible light and thermal condition, and it was proved to be scalable, efficient, and economical.
- Bazyar, Zahra,Hosseini-Sarvari, Mona
-
supporting information
p. 2282 - 2288
(2019/04/03)
-
- Pyrazine dicarboxylate-bridged arsenotungstate: Synthesis, characterization, and catalytic activities in epoxidation of olefins and oxidation of alcohols
-
A praseodymium(iii)-containing arsenotungstate K16H15Li7[Pr2(H2O)3(pzdc)As3W29O103]2·38H2O (1) (pzdc = pyrazine-2,3-dicarboxylic acid) was synthesized by a conventional aqueous solution method and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and single crystal X-ray diffraction. Structural analysis revealed that compound 1 was constructed by two identical subunits {Pr2(H2O)3(AsW9O33)3W2O4} bridged together by two pzdc ligands. In addition, compound 1 could act as an efficient catalyst for the epoxidation of olefins and oxidation of alcohols with hydrogen peroxide (H2O2) as the oxidant. In particular, the turnover frequency (TOF) in the oxidation of 1-phenylethanol reached up to 10170 h-1, which is higher than that of previously reported catalysts.
- Ma, Xinyi,He, Peipei,Xu, Baijie,Lu, Jingkun,Wan, Rong,Wu, Hechen,Wang, Yuan,Ma, Pengtao,Niu, Jingyang,Wang, Jingping
-
p. 12956 - 12963
(2019/09/07)
-
- Preparation method of nitroacetophenone
-
The invention discloses a preparation method of nitroacetophenone. The preparation method comprises the following step: by adopting nitrobenzoic acid as a material, carrying out three-step reaction ofacylating chlorination, condensation and hydrolysis to obtain a target product. The preparation method disclosed by the invention has the advantages that the reaction condition is mild, the aftertreatment is simple, and the problem of severe conditions of nitrating and oxidizing reactions in the traditional method is avoided; simultaneously, the preparation method has the advantages of less pollution and high yield and the like.
- -
-
Paragraph 0025
(2019/02/04)
-
- The synthesis of methyl triazole-4-carboxylate gold(I) complex and application on allene synthesis and alkyne hydration
-
The methyl 1H-1,2,3-triazole-4-carboxylate containing a strong electron-withdrawing group was developed and applied as a ligand for gold(I) cations. The resulting ester-triazole gold(I) complex was investigated for its efficiency in catalyzing allene synthesis and alkyne hydration, in which an excellent catalytic efficiency was observed with low catalyst loadings.
- Hu, Wenkang,Shan, Liang,Ma, Fudong,Zhang, Yilin,Yang, Yongchun,Wang, Dawei
-
-
- Highly selective aerobic oxidation of alkylarenes catalyzed by cobalt-based nanocatalyst in aqueous solution
-
The catalytic aerobic oxidation of alkylarenes catalyzed by cobalt supported on a highly crystalline γ-Al2O3 support (Co/Al2O3 nanocatalyst) is reported. The catalyst was prepared by a co-precipitation method and characterized using scanning and high-resolution transmission electron microscopies, energy-dispersive X-ray spectroscopy, X-ray diffraction and surface area measurements. A wide range of alkylarenes were converted to corresponding ketones. The catalyst can be recovered by simple filtration is recyclable for up to six consecutive runs.
- Albadi, Jalal,Alihosseinzadeh, Amir,Jalali, Mehdi,Mansournezhad, Azam
-
-
- 3 - Methyl - 1 H - indazole synthesis process
-
The invention relates to a synthesizing process of 3-methyl-1 H-indazole. The synthesizing process comprises the following steps: acetophenone is dropped into a sulfuric acid and nitric acid mixture solution, then calcium metasilicate powder is added, the mixture is kept to be stirred at lower temperature and passes through the night, the mixture is added into ice water and filtered, and 2-nitroacetophenone is obtained; the 2-nitroacetophenone, iron powder and ammonium chloride are synthesized into white solid 2-aminoacetophenone; the 2-aminoacetophenone is added to hydrochloric acid, then an NaNO2 aqueous solution is added, the mixture is stirred, then a hydrochloric acid solution of SnCl2.H2O is added, the mixture is stirred, the mixture is added to ice water and filtered, and filtrate is adjusted to alkalescence, filtered and dried so that the 3-methyl-1 H-indazole is obtained. According to the synthesizing process of the 3-methyl-1 H-indazole, calcium silicate is taken as a catalyst, the yield of the 2-nitroacetophenone is increased remarkably, the raw material of calcium silicate is easy to obtain, the cost is low, the operation and the use are simple, later synthesis of 2-aminoacetophenone and the 3-methyl-1 H-indazole is further facilitated, and the synthesizing process is suitable for industrial large-scale synthesis of 3-methyl-1 H-indazole.
- -
-
Paragraph 0016; 0019; 0020
(2018/04/20)
-
- Design and Synthesis of Zirconium-Containing Coordination Polymer Based on Unsymmetric Indolyl Dicarboxylic Acid and Catalytic Application on Borrowing Hydrogen Reaction
-
Catalytic borrowing hydrogen reaction is a very attractive transformation in the field of C-alkylation reaction. In this work, a new Zr (Zirconium)-containing coordination polymer containing unsymmetric indolyl dicarboxylic acid 1-(carboxymethyl)-1H-indole-5-carboxylic acid (H2CIA) was synthesized by the way of a solvothermal synthetic route and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Nitrogen adsorption-desorption, fourier transform infrared spectroscopy and X-ray photoelectronic spectroscopy (XPS). The coordination polymer Zr-CIA was employed as the catalyst for C-alkylation of acetophenone derivatives in the presence of benzyl alcohol. In addition, Zr-CIA catalyst was also observed to be effective in the reaction of alcohols with alcohols and high yields of alkylation products were achieved. Mechanism investigations were also conducted to better understand the catalysts and transformations. Meanwhile, the Zr-CIA could be reused at least five times without a notable decrease in activity and selectivity. (Figure presented.).
- Hu, Xinyu,Zhu, Haiyan,Sang, Xinxin,Wang, Dawei
-
supporting information
p. 4293 - 4300
(2018/10/02)
-
- Cp*CoIII-Catalyzed Efficient Dehydrogenation of Secondary Alcohols
-
A novel, well-defined molecular Cp*CoIII complex was isolated and structurally characterized for the first time. The efficiency of this cobalt catalyst was demonstrated in the alcohol dehydrogenation and dehydrative coupling of secondary alcohols under mild conditions into ketones and ethers, respectively.
- Gangwar, Manoj Kumar,Dahiya, Pardeep,Emayavaramban, Balakumar,Sundararaju, Basker
-
supporting information
p. 2445 - 2448
(2018/09/10)
-
- Polyoxovanadate catalysts for oxidation of 1-phenyl ethanol: From the discrete [V4O12]4- and [V10O28]6- anions to the anionic [V6O17]:N4 n - Coordination polymer
-
Three polyoxovanadate-based hybrids {[Ru(phen)3]2[V4O12]}·13H2O (1), [Ru(phen)3]2[V10O28]·15H2O (2), and [Ru(phen)3]2[V6O17]Cl·11H2O (3) (phen = 1,10-phenanthroline) were prepared under hydrothermal conditions and characterized by electron paramagnetic resonance (EPR) spectroscopy, infrared spectroscopy (IR), powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis, X-ray photoelectron spectroscopy (XPS), and single crystal X-ray diffraction analysis. Although the structures of both the cyclic vanadate [V4O12]4- and the [V10O28]6- anions are well-known, interestingly, a novel 1-dimensional (1-D) coordination polymer [V6O17]n4n- anion was constructed from tetranuclear [V4O12]4- and dinuclear [V2O7]4- building blocks, which were linked alternately through corner-shared oxygen atoms. Furthermore, the negative charges of polyoxovanadate [V4O12]4-, [V10O28]6- and [V6O17]4- anions were balanced by two [Ru(phen)3]2+/3+ complex cations. The catalytic properties of compounds 1-3 for the oxidation of 1-phenyl ethanol by tert-butyl hydroperoxide (TBHP) were investigated, and the results demonstrated that 1 and 3 exhibited excellent catalytic activities for the oxidation of 1-phenyl ethanol under mild catalytic conditions.
- Wang, Ke,Xu, Qiaofei,Ma, Pengtao,Zhang, Chao,Wang, Jingping,Niu, Jingyang
-
p. 6273 - 6279
(2018/10/23)
-
- Pd(II)-Catalyzed Denitrogenative and Desulfinative Addition of Arylsulfonyl Hydrazides with Nitriles
-
A Pd(II)-catalyzed denitrogenative and desulfinative addition of arylsulfonyl hydrazides with nitriles has been successfully achieved under mild conditions. This transformation is a new method for the addition reaction to nitriles with arylsulfonyl hydrazides as arylating agent, thus providing an alternative synthesis of aryl ketones. The reported addition reaction is tolerant to many common functional groups, and works well in the presence of electron-donating and electron-withdrawing substituents. Notably, the reported denitrogenative and desulfinative addition was also appropriate for alkyl nitriles, making this newly developed transformation attractive.
- Meng, Mengting,Yang, Liangfeng,Cheng, Kai,Qi, Chenze
-
p. 3275 - 3284
(2018/03/25)
-
- Preparation method of aromatic ketone
-
The invention discloses a preparation method of aromatic ketone. Under the effects of a palladium catalyst and a nitrogen-containing ligand, nitrile compounds and arylsulfonylhydrazide take desulfurization addition reaction in an organic solvent; after the reaction is completed, post treatment is performed to obtain aromatic ketone. The reaction is applicable to aromatic nitrile compounds, and isalso applicable to aliphatic nitrile compounds; the reaction realizes the wide substrate applicability and functional group tolerance; the potential application value is realized in the aspect of aryl-carbonyl building.
- -
-
Paragraph 0056; 0057; 0058; 0060
(2018/09/11)
-
- Cobaloxime-catalyzed hydration of terminal alkynes without acidic promoters
-
Cobaloxime (Co(dmgBF2)2·2H2O), an inexpensive first-row transition-metal complex, catalyzed hydration of terminal alkynes gave the corresponding methyl ketones in good to excellent yields under neutral conditions (additional protic acids and silver salts are not required). A wide range of functional groups, such as allyl ether, benzyl ethers, carboxylic esters, imides, amides, nitro, and halogens, were tolerated. The mild reaction conditions together with the inexpensive feature and easy availability of the catalyst well address the current challenges in the field of alkyne hydration.
- Hou, Shengtai,Yang, Hongjian,Cheng, Bin,Zhai, Hongbin,Li, Yun
-
supporting information
p. 6926 - 6929
(2017/07/10)
-
- A 1H-indazole derivatives preparation method
-
The invention provides a method for preparing 3-methyl-5-R-1H-indazole easily, safely and efficiently without performing any hydrazine hydrate reflux heating reaction or purifying a product and making the product pass through a column. The method at least comprises the following steps of: a, performing a diazo-reaction on 2-amino-5-R-hypnone serving as a raw material or an intermediate under the condition of an acid solution to generate a diazo salt; b, slowly adding a stannous chloride-hydrate hydrochloric acid solution into the diazo salt obtained in the step a for reacting to generate a 3-methyl-5-R-1H-indazole solution; and c, cooling the solution obtained in the step b under the condition that the pH value is 8-9, and precipitating a product out, wherein R in the steps above represents H or a halogen element.
- -
-
Paragraph 0043-0046
(2017/02/24)
-
- Method for producing nitroacetophenone
-
The present invention relates to the field of chemical engineering, and discloses a method for producing nitroacetophenone. The method is as below: pumping nitro ethylbenzene and a catalyst into an oxidation reactor, vacuumizing, substituting by oxygen, introducing oxygen in the oxidation reactor, controlling the oxygen pressure and flow, stirring the materials in the reactor, heating the reactor by steam, ceasing the heating after the reaction begins, cooling, and controlling the reaction temperature at 130-140 DEG C; when the ketone content reaches 80-85%, pressurizing the oxidation reaction oil into an acid removal kettle by the residual pressure into in the oxidation reactor, stirring, adjusting the pH value, stirring again, allowing to stand, and layering; discharging a nitrobenzene sodium formate solution to a reservoir to be recover nitrobenzoic acid; and pressurizing the oxidation reaction oil to a crystallization reactor, refrigerating, cooling, crystallizing, centrifuging, conducting spinning filter, washing and drying to obtain the nitroacetophenone product. The method of the invention eliminates exhaust emission, and has the advantages of rapid response, short cycle, and high conversion and yield of product.
- -
-
Paragraph 0051; 0052
(2016/10/31)
-
- Design and Synthesis of Alanine Triazole Ligands and Application in Promotion of Hydration, Allene Synthesis and Borrowing Hydrogen Reactions
-
A new type of alanine triazole (ATA) ligand was found to be an efficient partner for the stabilization of gold(III), thus rendering improved stability and high catalytic activities in allene synthesis and hydration reactions through the 3,3′-arrangement of propargyl esters and propargyl alcohols. In addition to Au(I), ATA-gold(III) was also proven to be an effective catalyst in promoting the formation of allenes with high yields. Furthermore, alanine triazole ruthenium has exhibited excellent potential as a means to catalyze borrowing hydrogen of alcohols and amines, ketones and alcohols.
- Yang, Yongchun,Qin, Anni,Zhao, Keyan,Wang, Dawei,Shi, Xiaodong
-
supporting information
p. 1433 - 1439
(2016/05/19)
-
- Selective oxidation of alkylbenzenes to aryl ketones with polymer-supported molybdenum catalyst
-
A new polymer-supported molybdenum-3,5-dimethyl pyrazole catalyst was synthesized and the structure was characterized by FT-IR and SEM. The resulting catalyst presented high activity for selective oxidation of alkyl aromatics to benzylic ketones with tert-butyl hydroperoxide and could be reused at least five times without loss of activity.
- Xu,Li,Chen
-
p. 3555 - 3558
(2015/12/30)
-
- An organocatalytic process for the hydrolytic cleavage of dithianes mediated by imidazolium ions: No harsh agents required
-
A new, organocatalytic approach to the hydrolytic deprotection of dithianes has been developed involving a low-toxicity imidazolium-ion-based catalyst in an aqueous medium. A complimentary solvent-free method without added water and involving a sacrificial aldehyde is also reported. The catalyst does not appear to operate by a specific-acid catalysis mechanism.
- Myles, Lauren,Gathergood, Nicholas,Connon, Stephen J.
-
supporting information
p. 188 - 194
(2015/02/02)
-
- Oxidation of alkylaromatics to aromatic ketones catalyzed by metalloporphyrins under the special temperature control method
-
The aerobic oxidation of alkylaromatics to aromatic ketones catalyzed by metalloporphyrins under the special temperature control method was systematically investigated. Three novel and key points were found to have significant functions in this process, that is, the special temperature control method (initiation at higher temperature and reaction at lower temperature), the synergistic effect of the composite catalysts comprising cobalt and manganese porphyrins, and the amount of catalysts in the reaction. Subsequently, the effects of substitutes on alkylaromatics were also explored under the same conditions. Results showed that alkylaromatic conversions gradually increased from 8.5% to 54.3% with the para-substituents shifting from the electron-donating group to the electron-withdrawing group (i.e., methoxy hydro bromo acyl nitro). A possible mechanism for this reaction was also proposed.
- Wang, Pan,She, Yuanbin,Fu, Haiyan,Zhao, Wenbo,Wang, Meng
-
p. 1059 - 1065
(2015/01/08)
-
- CONTINUOUS TWO STEP FLOW SYNTHESIS OF M-AMINO ACETOPHENONE
-
Disclosed herein is a continuous tubular reactor based conversion of acetophenones to amino substituted acetophenones wherein the nitration is carried out at ?10 to 10° C. followed by reduction to m-nitrophenone resulting in uniform output of product, said process comprising the steps of: a) Nitrating acetophenone with nitrating agent (nitration mixture or fuming nitric acid) at ?10 to 10° C.; b) Isolating m-nitro acetophenone from a mixture of o and m-nitro acetophenone and c) Reducing the m-nitro to obtain m-amino acetophenone.
- -
-
Paragraph 0062-0068
(2014/09/03)
-
- Manganese-catalyzed selective oxidation of aliphatic C-H groups and secondary alcohols to ketones with hydrogen peroxide
-
An efficient and simple method for selective oxidation of secondary alcohols and oxidation of alkanes to ketones is reported. An in situ prepared catalyst is employed based on manganese(II) salts, pyridine-2-carboxylic acid, and butanedione, which provides good-to-excellent conversions and yields with high turnover numbers (up to 10 000) with H2O2 as oxidant at ambient temperatures. In substrates bearing multiple alcohol groups, secondary alcohols are converted to ketones selectively and, in general, benzyl C-H oxidation proceeds in preference to aliphatic C-H oxidation. Manganeasy! MnII, picolinic acid, and butanedione make a smart mix for oxidation of secondary alcohols and alkanes and especially benzylic groups to ketones at room temperature with near stoichiometric amounts of hydrogen peroxide, low catalyst loadings, and high turn-over numbers. Copyright
- Dong, Jia Jia,Unjaroen, Duenpen,Mecozzi, Francesco,Harvey, Emma C.,Saisaha, Pattama,Pijper, Dirk,De Boer, Johannes W.,Alsters, Paul,Feringa, Ben L.,Browne, Wesley R.
-
p. 1774 - 1778
(2013/10/21)
-
- CONTINUOUS TWO STEP FLOW SYNTHESIS OF M-AMINO ACETOPHENONE
-
Disclosed herein is a continuous tubular reactor based conversion of acetophenones to amino substituted acetophenones wherein the nitration is carried out at -10 to 10 °C followed by reduction to m-nitrophenone resulting in uniform output of product, said process comprising the steps of: a) Nitrating acetophenone with nitrating agent (nitration mixture or fuming nitric acid) at -10 to 10 °C; b) Isolating m-nitro acetophenone from a mixture of o and m-nitro acetophenone and c) Reducing the m-nitro to obtain m-amino acetophenone.
- -
-
Page/Page column 10-11
(2013/04/25)
-
- Palladium-catalyzed chelation-assisted aromatic C-H nitration: Regiospecific synthesis of nitroarenes free from the effect of the orientation rules
-
A palladium-catalyzed chelation-assisted ortho-nitration of aryl C-H bond is described. A range of azaarenes such as 2-arylquinoxalines, pyridines, quinoline, and pyrazoles were nitrated with excellent chemo- and regioselectivity. Using the O-methyl oximyl group as a removable directing group, the regiospecific synthesis of a variety of o-nitro aryl ketones was achieved starting from aryl ketones via a three-step process involving the Pd-catalyzed ipso-nitration of C-H bond as a key step. Mechanistic investigations support a silver-mediated radical mechanism involving Pd((II/III) and/or Pd(II/IV) catalytic cycles under oxidizing conditions.
- Zhang, Wei,Lou, Shaojie,Liu, Yunkui,Xu, Zhenyuan
-
p. 5932 - 5948
(2013/07/26)
-
- Highly active mesoporous chromium silicate catalysts in side-chain oxidation of alkylaromatics
-
We approach a green method in the production of alkylaromatic ketones over hexagonally ordered mesoporous CrSBA-15 catalysts, which were used, in green routes, in the liquid-phase oxidation of alkylaromatics. A promising chemical treatment method was used with ammonium acetate solution to remove the toxic nature of non-framework chromium oxides deposited on the surface of calcined CrSBA-15(8), and the obtained green mesoporous CrSBA-15(8) catalyst was used to find its catalytic activity while the recyclability of mesoporous CrSBA-15 catalysts was also studied. Particularly, the mesoporous CrSBA-15 catalysts synthesized with a variety of chromium contents were extensively used in the production of acetophenone (APO) with various reaction parameters. On the basis of all catalytic results, the mesoporous CrSBA-15(8) catalyst produced a higher selectivity of alkylaromatic ketones (76-100%) as compared to other CrSBA-15 catalysts and was found to be a highly active, recyclable and promising heterogeneous catalyst for selective synthesis of alkylaromatic ketones. The Royal Society of Chemistry 2012.
- Selvaraj,Park,Kim,Kawi,Ha
-
p. 14204 - 14210
(2013/01/15)
-
- Microwave-assisted one-step synthesis of acetophenones via palladium-catalyzed regioselective arylation of vinyloxytrimethylsilane
-
The regiochemistry of the palladium-mediated arylation (Heck arylation) of enol ethers is sensitive to the structure of the enol ether, the arylating agent and the catalytic system. In this study, an effective and practical method was successfully developed for the synthesis of acetophenones with high regioselectivity under palladium-catalyzed conditions. A variety of acetophenones was readily prepared from aryl iodides in good to excellent yields under microwave irradiation in a single step. The key feature of our new protocol is the use of vinyloxytrimethylsilane as a highly regioselective acylation reagent. Copyright
- Qian, Wangke,Zhang, Lei,Sun, Haifeng,Jiang, Hualiang,Liu, Hong
-
supporting information
p. 3231 - 3236
(2013/01/15)
-
- Gaseous nitrogen dioxide for sustainable oxidative deprotection of trimethylsilyl ethers
-
In this study, trialkylsilyl ethers of indispensable protected alcohols are oxidatively deprotected in neat form with gaseous nitrogen dioxide (NO 2). Quantitative yields of aldehydes or ketones are obtained without the necessity of chromatography. The byproducts, nitrogen monoxide, anhydrous nitric acid, and hexamethyldisiloxane, can be quantitatively separated by evaporation and distillation in closed systems for recycling or further use. The direct new method supersedes the previous techniques that produce dangerous wastes and require chromatographic workup, while the atmospheric gas NO 2 and its gaseous reduction products are easily kept in closed systems until further use. Copyright Taylor and Francis Group, LLC.
- Javaheri, Mehdi,Naimi-Jamal, M. Reza,Dekamin, Mohammad G.,Kaupp, Gerd
-
experimental part
p. 142 - 148
(2012/03/26)
-
- Convenient and scalable process for the preparation of indole via raney nickel-catalyzed hydrogenation and ring closure
-
An efficient and practical method for the synthesis of indole as a key starting material for many useful chemicals is described. Using 2-nitrotoluene as starting material, hydroxymethylation with formaldehyde under alkaline conditions gave 2-(2-nitrophenyl) ethanol on a large scale. Raney Ni catalyst was used for both reduction of the nitro group as well as for the indole formation. The overall yield was 78% from 2-nitrotoluene. Copyright
- Guo, Xianghai,Peng, Zhiliang,Jiang, Shende,Shen, Jiaxiang
-
scheme or table
p. 2044 - 2052
(2011/08/03)
-
- A silica supported cobalt (II) Salen complex as efficient and reusable catalyst for the selective aerobic oxidation of ethyl benzene derivatives
-
A silica supported cobalt (II) Salen complex catalyst has been successfully employed in the aerobic oxidation of alkyl aromatics at atmospheric pressure in the presence of N-hydroxyphthalimide (NHPI). The reaction is particularly selective for the oxidation of the benzylic CH2 group and the major product obtained was ketone. The immobilized catalyst can be easily recovered and reused for at least four reaction cycles without any significant loss of its catalytic activity.
- Rajabi, Fatemeh,Luque, Rafael,Clark, James H.,Karimi, Babak,MacQuarrie, Duncan J.
-
experimental part
p. 510 - 513
(2011/12/15)
-
- Ethylammonium nitrate (EAN)/Tf2O and EAN/TFAA: Ionic liquid based systems for aromatic nitration
-
Acting as in situ sources of triflyl nitrate (TfONO2) and trifluoroacetyl nitrate (CF3COONO2), the EAN/Tf 2O and EAN/TFAA systems, generated via metathesis in the readily available ethylammonium nitrate (EAN) ionic liquid as solvent, are powerful electrophilic nitrating reagents for a wide variety of aromatic and heteroaromatic compounds. Comparative nitration experiments indicate that EAN/Tf2O is superior to EAN/TFAA for nitration of strongly deactivated systems. Both systems exhibit low substrate selectivity (K T/KB = 5-10) in (Figure presented) between values reported for covalent nitrates and preformed nitronium salts.
- Aridoss, Gopalakrishnan,Laali, Kenneth K.
-
experimental part
p. 8088 - 8094
(2011/11/13)
-
- Candida tenuis xylose reductase catalysed reduction of acetophenones: The effect of ring-substituents on catalytic efficiency
-
The catalytic efficiencies of Candida tenuis xylose reductase catalysed reductions of mono-substituted acetophenones are in reasonable correlation with the σ-Hammett coefficients of the substituted phenyl groups. Variations of the substrate transformation rates are hence mainly caused by mesomeric and inductive effects of the substituents, while differences in substrate binding have a secondary relevance. Some substrate 1H NMR chemical shifts and carbonyl IR absorption bands are in reasonable accordance with the catalytic activities and allow the estimation of the transformation rates with good accuracy. The resulting substituted (S)-1-phenyl ethanols are generated in very high enantiomeric excess.
- Vogl, Michael,Kratzer, Regina,Nidetzky, Bernd,Brecker, Lothar
-
experimental part
p. 5863 - 5870
(2011/09/30)
-
- Regiospecific synthesis of nitroarenes by palladium-catalyzed nitrogen-donor-directed aromatic C-H nitration
-
Nitration of N-heteroaromatics: The first example of palladium-catalyzed direct ortho-nitration of aryl C-H bonds is described. A range of azaarenes, such as 2-arylquinoxalines, pyridines, pyrazoles, and O-methyl oximes, were nitrated with excellent chemo- and regioselectivity (see scheme; DCE=1,2-dichloroethane). Preliminary mechanistic investigations support a silver-mediated radical mechanism involving palladium(II/III) and/or palladium(II/IV) catalytic cycles under oxidizing conditions. Copyright
- Liu, Yun-Kui,Lou, Shao-Jie,Xu, Dan-Qian,Xu, Zhen-Yuan
-
p. 13590 - 13593
(2011/03/18)
-
- A facile, catalytic deoximation method using potassium bromide and ammonium heptamolybdate in the presence of hydrogen peroxide in an aqueous medium
-
A simple, mild and efficient procedure for the cleavage of a wide range of ketoximes and aldoximes to the corresponding carbonyl compounds in an aqueous medium using catalytic amounts of potassium bromide and ammonium heptamolybdate tetrahydrate in combination with 30% hydrogen peroxide is described. Georg Thieme Verlag Stuttgart.
- Ganguly, Nemai C.,Barik, Sujoy Kumar
-
p. 425 - 428
(2008/09/20)
-
- An efficient procedure for the TEMPO-catalyzed oxidation of alcohols to aldehydes and ketones using ferric chloride hexahydrate as terminal oxidant
-
A simple, efficient procedure for the oxidation of alcohols by catalytic 2,2,6,6-tetramethyl-piperidyl-l-oxy (TEMPO) was developed using FeCl 3·6H2O as the terminal oxidant. The reaction gives high yield of the corresponding aldehydes and ketones with no over oxidation to the acid.
- Kumar, R. Senthil,Karthikeyan,Perumal, Paramasivan T.
-
p. 720 - 725
(2008/09/21)
-
- Microwave assisted rapid and efficient synthesis of aryl methyl ketones and β-keto esters using Meldrum's acid
-
Microwave mediated rapid and efficient synthesis of aryl methyl ketones and β-keto esters from acyl Meldrum's acid by hydrolysis and alcoholysis, respectively, has been reported.
- More,Mahulikar
-
p. 823 - 825
(2007/10/03)
-
- Bismuth-catalyzed benzylic oxidations with tert-butyl hydroperoxide
-
(Chemical Equation Presented) Oxidation of alkyl and cycloalkyl arenes with tert-butyl hydroperoxide catalyzed by bismuth and picolinic acid in pyridine and acetic acid gave the corresponding benzylic ketones (48-99%). Alternatively, oxidation of methyl arenes gave the corresponding substituted benzole acids (50-95%). Preliminary mechanistic studies were consistent with a radical mechanism rather than a bismuth(III)-bismuth(V) cycle.
- Bonvin, Yannick,Callens, Emmanuel,Larrosa, Igor,Henderson, David A.,Oldham, James,Burton, Andrew J.,Barrett, Anthony G. M.
-
p. 4549 - 4552
(2007/10/03)
-
- Lewis acid assisted permanganate oxidations
-
Lewis acids combine with permanganate in acetone solutions to form a complex that has enhanced oxidizing capabilities. The use of Lewis acids under these conditions to promote permanganate oxidations is superior to the use of Bronsted acids because the latter promote enolization of the solvent and subsequent unproductive reduction of the oxidant. The products obtained from a variety of alkenes, alkynes, arenes, sulfides, alcohols and ethers have been identified and probable reaction mechanisms proposed.
- Lai, Sheng,Lee, Donald G.
-
p. 9879 - 9887
(2007/10/03)
-
- Scandium(III) trifluoromethanesulfonate catalyzed aromatic nitration with inorganic nitrates and acetic anhydride
-
The rare earth metal(III) trifluoromethanesulfonate (rare earth metal(III) triflate, RE(OTf)3) was found to be an efficient catalyst for aromatic nitration with carboxylic anhydride-inorganic nitrate as the nitrating agent. In the presence of a catalytic amount of RE(OTf)3, the nitration of substituted benzenes proceeded to afford the corresponding nitrobenzenes. Especially, scandium(III) trifluoromethanesulfonate (scandium(III) triflate, Sc(OTf)3) is the most active catalyst among our tested Lewis acids. It was also found that acetic anhydride-Al(NO 3) · 9H2O is the most active nitrating agent in this system.
- Kawada, Atsushi,Takeda, Shigemitsu,Yamashita, Kazumi,Abe, Hitoshi,Harayama, Takashi
-
p. 1060 - 1065
(2007/10/03)
-
- Photoactive materials applicable to imaging systems
-
Organic photoprecursors of amines are provided for use in photosensitive imaging systems, finding particular application in the preparation of lithographic printing plates. Said photoprecursors generate free amines on exposure to long wavelength UV or visible radiation, have high solubility in organic solvents, and include photolabile 2-nitrobenzyl functional groups. Methods for the synthesis of the photoprecursors are described, and the use of the said photoprecursors for the production of printing plates using both positive working and negative working techniques are discussed.
- -
-
Page column 13
(2010/02/05)
-
- A fast and mild method for the nitration of aromatic rings
-
The use of N2O5 and a Fe(III) catalyst for the nitration of aromatic rings is described. This methodology is compatible with most functional groups and results in near quantitative yields in 4 min. The reaction conditions are non-oxidising: benzaldehyde and benzyl alcohols are readily nitrated with little or no oxidation (4%) occurring. The addition of the iron catalyst activates the system to such an extent that nitration of an activated aromatic ring, such as toluene, occurs quantitatively at -100°C. This high activity allows compounds with sensitive functional groups such as alkenes to be smoothly nitrated.
- Bak, Radoslaw R.,Smallridge, Andrew J.
-
p. 6767 - 6769
(2007/10/03)
-