- Asymmetric Counter-Anion-Directed Aminomethylation: Synthesis of Chiral β-Amino Acids via Trapping of an Enol Intermediate
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A novel enantioselective aminomethylation reaction of diazo compound, alcohol and α-aminomethyl ether enabled by asymmetric counteranion-directed catalysis is disclosed that offers an efficient and convenient access to furnish optically active α-hydroxyl-β-amino acids in high yield with high to excellent enantioselectivities. Control experiments and DFT calculations indicate that the transformation proceeds through trapping the in situ generated enol intermediate with methylene iminium ion, and the asymmetric induction was enabled by chiral pentacarboxycyclopentadiene anion via H-bonding and electrostatic interaction.
- Kang, Zhenghui,Wang, Yongheng,Zhang, Dan,Wu, Ruibo,Xu, Xinfang,Hu, Wenhao
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- Liberation of acrylates from nickelalactones via Ni─O ring opening with alkyl iodides
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The utilization of carbon dioxide as a feedstock for the production of raw chemicals is of high current industrial interest. One attractive reaction is the transformation of carbon dioxide into acrylic acid or acrylates. The cleavage of the Ni─O bond of nickelalactones may result in the formation of acrylates. In this work, C2H5I, CF3CH2I and CF3I are studied as alkylation reagents for the Ni─O ring opening of nickelalactones. The results indicate that both C2H5I and CF3CH2I are able to release acrylates from nickelalactones. Based on the experimental evidence and literature precedents, a mechanism – proceeding via Ni─O ring opening of nickelalactone, β-H elimination to release the acrylate and reductive elimination for recovery of the Ni(0) species – is proposed.
- Zhang, Zhizhi,Guo, Fangjie,Kühn, Fritz E.,Sun, Jing,Zhou, Mingdong,Fang, Xiangchen
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- Homogeneous and Heterogeneous Catalyzed Esterification of Acrylic Acid with Ethanol: Reaction Kinetics and Modeling
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Kinetics of esterification of acrylic acid with ethanol in the presence of homogeneous (H2SO4, HCl, p-TSA, HI) catalysts as well as heterogeneous catalysts (Dowex 50WX, Amberlyst 15) was studied. The effects and performance of these catalysts on the conversion of acrylic acid were evaluated. In the kinetics of homogeneous catalyzed reaction, both concentration and activity-based model were employed. Activity coefficients were predicted by the Universal Functional group Contribution (UNIFAC) method to consider nonideal behavior of the liquid phase. The heterogeneous catalyzed reaction mechanisms were developed using Eley–Rideal theory. The model results were compared with the experimental results and were in good agreement. The temperature dependency of the constants, reaction enthalpy, and entropy, and activation energy were determined. The conversion of acrylic acid was obtained as 63.2%, 61.02%, 53.3%, 21.4%, 34.96%, and 14.84% for H2SO4, p-TSA, HCl, HI, Dowex 50WX, and Amberlyst 15, respectively, under process temperature of 70°C, reactant molar ratio of 1:1, and catalyst concentration of 2% (v/v) for homogeneous and 2.17 g for heterogeneous catalyst. These outcomes provide an approach to understand the significant effect of each catalyst on the esterification kinetics of acrylic acid and ethanol.
- Jyoti, Ghoshna,Keshav, Amit,Anandkumar,Bhoi, Stutee
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- Efficient and selective conversion of methyl lactate to acrylic acid using Ca3(PO4)2-Ca2(P2O 7) composite catalysts
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Calcium phosphate Ca3(PO4)2 and calcium pyrophosphate Ca2(P2O7) composite catalysts of different weight ratios were prepared by a slurry-mixing method. These composite catalysts were calcined at 500 °C in air and characterized by N2 sorption for specific surface area by XRD for crystal phases and by TPD-NH 3 (acidity), TPD-CO2 (basicity) and SEM for morphological features. All the Ca3(PO4)2-Ca 2(P2O7) composite catalysts were found to be active in the vapor phase conversion of methyl lactate (ML) to give mainly acrylic acid (AA) and methyl acrylate (MA) as products. The catalyst Ca 3(PO4)2-Ca2(P2O 7) of 50:50 wt% ratio was the most efficient and selective catalyst in the conversion of ML, which gave 91% conversion of ML with selectivity for AA (75%) and MA (5%) together (80%) under optimized reaction conditions. The higher conversion of ML and formation of AA by Ca3(PO 4)2-Ca2(P2O7) [50:50 wt%] composite catalyst has been attributed to moderate acid-base strength regulated with surface properties.
- Hong, Ju Hyeong,Lee, Jong-Min,Kim, Hyungrok,Hwang, Young Kyu,Chang, Jong-San,Halligudi, Shiva B.,Han, Yo-Han
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- WITTIG-HORNER REACTION CATALYZED BY ACTIVATED BARIUM HYDROXIDE IN THE PRESENCE OF ULTRASOUND
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The sonochemical Wittig-Horner reaction, catalyzed by an activated barium hydroxide catalyst in interfacial solid-liquid conditions leads to E-acrylates with very good yields.The sonochemical process takes place at room temperature and with lower catalyst weight and reaction time than the thermal process.
- Fuentes, A.,Marinas, J.M.,Sinisterra, J.V.
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- Controlling the Lewis Acidity and Polymerizing Effectively Prevent Frustrated Lewis Pairs from Deactivation in the Hydrogenation of Terminal Alkynes
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Two strategies were reported to prevent the deactivation of Frustrated Lewis pairs (FLPs) in the hydrogenation of terminal alkynes: reducing the Lewis acidity and polymerizing the Lewis acid. A polymeric Lewis acid (P-BPh3) with high stability was designed and synthesized. Excellent conversion (up to 99%) and selectivity can be achieved in the hydrogenation of terminal alkynes catalyzed by P-BPh3. This catalytic system works quite well for different substrates. In addition, the P-BPh3 can be easily recycled.
- Geng, Jiao,Hu, Xingbang,Liu, Qiang,Wu, Youting,Yang, Liu,Yao, Chenfei
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p. 3685 - 3690
(2021/05/31)
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- Acid- And base-switched palladium-catalyzed γ-C(sp3)-H alkylation and alkenylation of neopentylamine
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The functionalization of remote unactivated C(sp3)-H and the reaction selectivity are among the core pursuits for transition-metal catalytic system development. Herein, we report Pd-catalyzed γ-C(sp3)-H-selective alkylation and alkenylation with removable 7-azaindole as a directing group. Acid and base were found to be the decisive regulators for the selective alkylation and alkenylation, respectively, on the same single substrate under otherwise the same reaction conditions. Various acrylates were compatible for the formation of C(sp3)-C(sp3) and C(sp3)-C(sp2) bonds. The alkenylation protocol could be further extended to acrylates with natural product units and α,β-unsaturated ketones. The preliminary synthetic manipulation of the alkylation and alkenylation products demonstrates the potential of this strategy for structurally diverse aliphatic chain extension and functionalization. Mechanistic experimental studies showed that the acidic and basic catalytic transformations shared the same six-membered dimer palladacycle.
- Zhang, Jinquan,Zhang, Shuaizhong,Zou, Hongbin
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supporting information
p. 3466 - 3471
(2021/05/31)
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- Phosphine-Catalyzed Cascade Annulation of MBH Carbonates and Diazenes: Synthesis of Hexahydrocyclopenta[c]pyrazole Derivatives
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A phosphine-catalyzed cascade annulation of Morita-Baylis-Hillman (MBH) carbonates and diazenes was achieved, giving tetrahydropyrazole-fused heterocycles bearing two five-membered rings in moderate to excellent yields. The reaction underwent an unprecedented reaction mode of MBH carbonates, in which two molecules of MBH carbonates were fully merged into the ring system.
- Guo, Hongchao,Li, Hongxiang,Liu, Hao,Shi, Wangyu,Wang, Chang,Wang, Wei,Wu, Yongjun
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supporting information
p. 5571 - 5575
(2021/07/31)
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- METHOD FOR PRODUCING α,β-UNSATURATED CARBOXYLIC ACID DERIVATIVE
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To provide a method for producing α,β-unsaturated carboxylic acid derivative that is advantageous in a cost and efficient.SOLUTION: A method for producing α,β-unsaturated carboxylic acid derivative including: a process of allowing metal lactone compound and alkyl halide having the carbon number of 1 to 6 to react to obtain α,β-unsaturated carboxylic acid derivative and either or both of hydrogen iodide and hydrogen bromide; and a process of allowing either or both of the hydrogen iodide and hydrogen bromide and alcohol having the carbon number of 1 to 6 to react to regenerate the alkyl halide.SELECTED DRAWING: None
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Paragraph 0102; 0108; 0113; 0115
(2021/04/02)
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- Palladium-catalyzed remote C-H functionalization of 2-aminopyrimidines
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A straightforward strategy was developed for the arylation and olefination at the C5-position of the N-(alkyl)pyrimidin-2-amine core with readily available aryl halides and alkenes, respectively. This approach was highly regioselective, and the transformation was achieved based on two different (Pd(ii)/Pd(iv)) and (Pd(0)/Pd(ii)) catalytic cycles.
- Das, Animesh,Jana, Akash,Maji, Biplab
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supporting information
p. 4284 - 4287
(2020/04/27)
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- Synthesis of Some Aromatic and Aliphatic Esters Using WO3/ZrO2 Solid Acid Catalyst under Solvent Free Conditions
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A simple method is delineated for the synthesis of substituted ester products in superior yields by esterification reaction under solvent unbound condition using tungsten upgraded ZrO2 solid acid catalyst at 353 K. The WO3/ZrO2 catalyst has been prepared by using impregnation method followed by calcination at 923 K over a period of 6 h in air atmosphere. SEM, XRD, FTIR, and BET surface area techniques were used to categorize this catalyst. Zirconia has both acidic and basic possessions which can be changed by incorporating suitable promoter atom like tungsten which in turn increases the surface area thereby enhancing the surface acidity. Impregnation of W6+ ions exhibits a strong influence on phase modification of zirconia from thermodynamically solid monoclinic to metastable tetragonal phase. Amalgamation of promoter W6+ will stabilize tetragonal phase which is active in catalyzing reactions. In esterification reaction WO3/ZrO2 catalyst was found to be stable, efficient and environmental friendly, effortlessly recovered by filtration, excellent yield of product and can be reusable efficiently.
- Guguloth, Vijaya Charan,Battu, Satyanarayana
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p. 2153 - 2157
(2020/09/16)
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- Palladium Nanoparticle-Catalyzed Stereoselective Domino Synthesis of 3-Allylidene-2(3 H)-oxindoles and 3-Allylidene-2(3 H)-benzofuranones
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A single-step, stereoselective protocol for the synthesis of unsymmetrically substituted (E)-3-allylideneoxindole and (E)-3-allylidenebenzofuran from readily accessible starting materials using palladium binaphthyl nanoparticles (Pd-BNPs) has been developed. Pd-BNP showing a wide range of functional group tolerance and an immense array of substrate scope have been explored with the successful synthesis of the drug molecule "tubulin polymerization inhibitor" free from trace metal impurities. The model reaction is extended to a gram-scale synthesis, and one of the products is utilized for derivatization. The Pd-BNP has been recycled up to 5 catalytic cycles without any loss in reaction yields and particle size of nanoparticles.
- Parveen, Naziya,Sekar, Govindasamy
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p. 4682 - 4694
(2020/05/08)
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- Second-Generation meta-Phenolsulfonic Acid-Formaldehyde Resin as a Catalyst for Continuous-Flow Esterification
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A second-generation m-phenolsulfonic acid-formaldehyde resin (PAFR II) catalyst was prepared by condensation polymerization of sodium m-phenolsulfonate and paraformaldehyde in an aqueous H2SO4 solution. This reusable, robust acid resin catalyst was improved in both catalytic activity and stability, maintaining the characteristics of the previous generation catalyst (p-phenolsulfonic acid-formaldehyde resin). PAFR II was applied in the batchwise and continuous-flow direct esterification without water removal and provided higher product yields in continuous-flow esterification than any other commercial ion-exchanged acid catalyst tested.
- Hu, Hao,Ota, Hajime,Baek, Heeyoel,Shinohara, Kenta,Mase, Toshiaki,Uozumi, Yasuhiro,Yamada, Yoichi M. A.
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supporting information
p. 160 - 163
(2020/01/02)
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- Palladium-catalyzed regioselective synthesis of B(4,5)-or B(4)-substituted: O-carboranes containing α,β-unsaturated carbonyls
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With the help of a carboxylic acid directing group, Pd-catalyzed regioselective synthesis of B(4,5)-or B(4)-substituted o-carboranes containing α,β-unsaturated carbonyls has been reported. The-COOH, removed during the course of the reaction, is responsible for controlling the regioselectivity. The desired products could be obtained in moderate to good yields.
- Li, Jiaoyi,Lu, Jian,Tian, Song,Wang, Qian,Zhang, Chuyi,Zhang, Jianwei,Zhou, Ling
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supporting information
p. 4723 - 4727
(2020/07/13)
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- Ruthenium(II) Catalysed Highly Regioselective C-3 Alkenylation of Indolizines and Pyrrolo[1,2-a]quinolines
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Discovered the Ruthenium(II) catalysed highly stereo- and regioselective protocol for the oxidative C-3 alkenylation of indolizines and pyrrolo[1,2-a]quinolines. The methodology represents the first example for the directing group assisted C–C bond formation reaction of the indolizines. Under mild reaction conditions, this method provides an ample substrate scope to produce C-3 alkenyl indolizines in excellent to moderate yields. However, pyrrolo[1,2-a]quinolines underwent alkenynation at elevated temperature to furnish C-3 alkenyl derivatives. The functionalized indolizines were selectively reduced to obtain their saturated derivatives.
- Jadhav, Pankaj Pandit,Kahar, Nilesh Machhindra,Dawande, Sudam Ganpat
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supporting information
p. 7831 - 7835
(2019/12/24)
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- Acrylonitrile Derivatives from Epoxide and Carbon Monoxide Reagents
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The present invention is directed to reactor systems and processes for producing acrylonitrile and acrylonitrile derivatives. In preferred embodiments of the present invention, the processes comprise the following steps: introducing an epoxide reagent and carbon monoxide reagent to at least one reaction vessel through at least one feed stream inlet; contacting the epoxide reagent and carbon monoxide reagent with a carbonylation catalyst to produce a beta-lactone intermediate; polymerizing the beta-lactone intermediate with an initiator in the presence of a metal cation to produce a polylactone product; heating the polylactone product under thermolysis conditions to produce an organic acid product; optionally esterifying the organic acid product to produce one or more ester products; and reacting the organic acid product and/or ester product with an ammonia reagent under ammoxidation conditions to produce an acrylonitrile product.
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Paragraph 0277-0280
(2019/01/15)
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- Tandem Remote Csp3-H Activation/Csp3-Csp3 Cleavage in Unstrained Aliphatic Chains Assisted by Palladium(II)
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We report here a proof-of-concept for the cleavage of unstrained remote Csp3-Csp3 bonds at room temperature assisted by a directing group, opening up new possibilities to use aliphatic carboxylic acids as suitable alkenyl coupling partners. This strategy involves the Pd-mediated Csp3-H activation directed by a tethered 8-aminoquinoline group, followed by a concerted asynchronous carbene insertion into the Pd-C bond, and an unexpected β-carbon-carbon bond splitting. The insertion of a coupling partner into a Pd-C bond is a novel route to promote C-C bond cleavage, which in contrast to most common methodologies does not rely on the use of strained carbocycles.
- Pérez-Gómez, Marta,Azizollahi, Hamid,Franzoni, Ivan,Larin, Egor M.,Lautens, Mark,García-López, José-Antonio
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supporting information
p. 973 - 980
(2019/03/04)
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- Preparation method of ramelteon
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The invention relates to the technical field of insomnia drugs, and discloses a preparation method of ramelteon. The method comprises the following step of: 1) adding triethyl phosphonoacetate and 400-600 ml of tetrahydrofuran into a 2L three-necked bottle and carrying out ice-water bath below 40 DEG C. According to the preparation method of ramelteon, ethyl acrylate and chloroform are stirred anddissolved, bromine is dropwise added at a normal temperature, bromine is dropwise added again after reaction is carried out for 1 hour, reaction is carried out for 2 hours, a water layer is extractedby concentrated hydrochloric acid, washing is carried out with water, saturated sodium hydrogen sulfite solution and saline water in sequence, anhydrous sodium sulfate is dried and filtered, and thefiltrate is decompressed and steamed to remove a solvent and then decompressed and dried below 60 DEG C so as to ensure that the reaction can be completely carried out, the purity of the prepared ramelteon is greatly improved, and the problems that the manufacture process is long in time, the ratio of the ramelteon in the extract is low, the preparation efficiency of the ramelteon is low and the preparation cost of the ramelteon is greatly increased are avoided.
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Paragraph 0021; 0022; 0026; 0027; 0031; 0032
(2019/01/17)
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- Ruthenium(II) oxidase catalysis for C-H alkenylations in biomass-derived γ-valerolactone
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Ruthenium(ii) biscarboxylate oxidase catalysis is a powerful tool for the assembly of functionalized arenes with oxygen as a green oxidant, but this strategy was thus far limited to its use in traditional organic solvents. Herein, we report on a green procedure for the ruthenium(ii) biscarboxylate-catalysed C-H functionalisation in biomass-derived γ-valerolactone as the reaction medium. The oxidase catalysis was characterized by ample substrate scope and proceeded efficiently with oxygen as the sole oxidant. The overall green nature of this C-H-activation methodology is reflected by H2O being the only by-product.
- Bechtoldt, Alexander,Baumert, Marcel E.,Vaccaro, Luigi,Ackermann, Lutz
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supporting information
p. 398 - 402
(2018/02/07)
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- Method for synthesizing low-carbon alcohol acrylate from acetylene through carbonylation
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The invention relates to a method for synthesizing low-carbon alcohol acrylate from acetylene through carbonylation. The method comprises steps as follows: acetylene, low-carbon alcohol and carbon monoxide are taken as raw materials and added to an organic solvent containing a nickel-based catalyst, low-carbon alcohol acrylate is directly synthesized from the mixture through carbonylation, whereinthe nickel-based catalyst comprises a main catalyst, an additive and a catalyst promoter, the main catalyst contains a nickel-containing compound and a multidentate ligand, the additive is triphenylphosphine, the chemical formula of the catalyst promoter is AlR(3-x)Clx, R is C2-C8 alkyl, and x is larger than or equal to 0 and smaller than or equal to 1. Compared with the prior art, the catalyticsystem is non-toxic and non-corrosion to equipment; yield of products at lower temperature and pressure is high, particularly, the catalyst system is low in cost and simple to prepare, cost of raw materials of production and operation cost can be greatly reduced, and the method has broad industrial application prospect.
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Paragraph 0033; 0034; 0037; 0038
(2018/05/30)
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- Enhanced Acrylate Production from 2-Acetoxypropanoic Acid Esters
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Reaction conditions and reactor geometry for producing acrylates in high yield from lactic acid-derived 2-acetoxypropanoic acid (APA) esters are presented. An acrylate ester yield of 75% is achieved from methyl and benzyl APA esters at 550 °C in a fixed bed reactor filled with nonporous silica particles, carbon dioxide as a diluent gas, and acetic acid as a co-feed with the APA ester. The yield from methyl and benzyl APA esters is remarkably higher than from ethyl or butyl esters of APA, which have hydrogen atoms on the β-carbon of the ester functional group and thus can undergo alkene elimination, leading to reduced acrylate yield. Under optimum conditions, APA conversion to acrylates is stable over 30 h of continuous operation with little carbon deposition on the contact material.
- Nezam, Iman,Peereboom, Lars,Miller, Dennis J.
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p. 715 - 719
(2017/05/29)
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- Method for carbonylation-synthesizing acrylic ester by acetylene
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The invention discloses a method for carbonylation-synthesizing acrylic ester by acetylene, and relates to the technical field of the organic synthesis. The method comprises the following steps: using the acetylene, carbon monoxide and lower alcohol as reaction raw materials, under the action of a catalyst, executing the acetylene carbonylation reaction in a solvent and directly generating the acrylic ester, wherein the catalyst is a nickel non-halogen compound and a salt ligand of Beta-diketone and corresponding compounds. An original method for synthesizing the acrylic ester has the problems, such as long reaction time, carbon deposition in the reaction process and serious corrosion of devices. The method has the advantages of easy acquisition of used catalyst components, rapid catalytic reaction speed, short used time, no carbon deposition in the reaction process, and no device corrosion by a catalyst system.
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Paragraph 0049; 0050
(2018/03/01)
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- Method for synthesizing acrylic acid low-carbon alcohol ester through carbonylation of acetylene
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The invention relates to a method for synthesizing acrylic acid low-carbon alcohol ester through carbonylation of acetylene. A nickel-containing compound and a bidentate ligand containing nitrogen and a VIA-th group element serve as catalysts, and acetylene, carbon monoxide and low-carbon alcohol are subjected to carbonylation reaction in a solvent to synthesize the acrylic ester at one step. The method has the characteristics of low catalyst cost, high reaction speed, no carbon deposition in the reaction process and the like.
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Paragraph 0035-0036
(2017/08/29)
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- PROCESSES FOR CONVERSION OF BIOLOGICALLY DERIVED MEVALONIC ACID
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The invention relates to a process comprising reacting mevalonic acid, or a solution comprising mevalonic acid, to yield a first product or first product mixture, optionally in the presence of a solid catalyst and/or at elevated temperature and/or pressure. The invention further relates to a process comprising: (a) providing a microbial organism that expresses a biosynthetic mevalonic acid pathway; (b) growing the microbial organism in fermentation medium comprising suitable carbon substrates, whereby biobased mevalonic acid is produced; and (c) reacting said biobased mevalonic acid to yield a first product or first product mixture.
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Paragraph 0136
(2016/06/13)
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- Hantzsch Ester as a Photosensitizer for the Visible-Light-Induced Debromination of Vicinal Dibromo Compounds
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The debromination of vicinal dibromo compounds to generate alkenes usually requires harsh reaction conditions and the addition of catalysts. Just recently the visible-light-induced debromination of vicinal dibromo compounds emerged as a possible alternative to commonly used methods, but the substrate scope of this reaction is limited and a photocatalyst is necessary for the successful conversion of the starting compounds. A catalyst-free visible-light-induced debromination of vicinal dibromo compounds with a base-activated Hantzsch ester as photosensitizer is reported. The method has a wide substrate scope and a broad functional-group compatibility.
- Chen, Wenxin,Tao, Huachen,Huang, Wenhao,Wang, Guoqiang,Li, Shuhua,Cheng, Xu,Li, Guigen
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supporting information
p. 9546 - 9550
(2016/07/14)
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- Reductive debromination of 1,2-dibromides with anisidines
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vic-Dibromides containing the α-bromocarbonyl or α-bromoaromatic moieties were reductively debrominated to furnish alkenes in high yields. o- and m-anisidines but not p-anisidine were found to be effective debrominating agents. The reductive debrominations were found to be trans-stereospecific.
- McGraw, Kristen M.,Bowler, Jeannette T.,Ly, Vy T.,Erden, Ihsan,Wu, Weiming
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p. 285 - 287
(2016/01/12)
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- System and method for preparing acrylic acid lower alcohol ester from acetylene
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The invention discloses a system and method for preparing acrylic acid lower alcohol ester from acetylene. The system comprises an acetylene dissolution tank, a reactor, a first gas-liquid separator, a second gas-liquid separator, a carbon monoxide extraction device and a compressor. The acetylene dissolution tank is provided with an acetylene inlet, a non-polar organic solvent inlet and a liquid outlet. The reactor comprises an acetylene solvent inlet, a carbon monoxide gas inlet and a gas outlet. The first gas-liquid separator comprises a gas inlet, a gas outlet and an acrylic acid lower alcohol ester outlet. The second gas-liquid separator comprises a gas inlet and a gas outlet. The product, by-products and a solvent can be separated by means of different distillation temperatures; besides, carbon monoxide and the organic solvent are recycled, so that raw materials are saved, and cost is lowered.
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Paragraph 0056; 0057
(2017/06/13)
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- Acrylates via Metathesis of Crotonates
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Crotonic acid has the potential to be produced from renewable resources at low cost but currently has a limited market. We are investigating catalytic routes to exploit the functionalities of crotonic acid to produce a range of established industrial chemicals. Here we report our work on converting crotonates to acrylates, where a cost-competitive bio-based alternative can provide a market advantage. Our optimized reaction conditions for the cross-metathesis between crotonates and ethylene resulted in an increase in catalyst turnover numbers by 2 orders of magnitude compared with literature values. Control experiments showed the cross-metathesis with ethylene to be an equilibrium reaction. The turnover-number-limiting factor was found to be the stability of the metathesis catalyst.
- Schweitzer, Dirk,Snell, Kristi D.
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supporting information
p. 715 - 720
(2015/07/27)
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- 1,4-Diazabicyclo[2.2.2]octane-Promoted Aminotrifluoromethylthiolation of α,β-Unsaturated Carbonyl Compounds: N-Trifluoromethylthio-4-nitrophthalimide Acts as Both the Nitrogen and SCF3 Sources
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A novel difunctionalization reaction is described. It uses N-trifluoromethylthio-4-nitrophthalimide as the reagent, which serves as both the nitrogen and SCF3 sources. In the presence of DABCO (1,4-diazabicyclo[2.2.2]octane), the nitrogen and SCF3 groups can be incorporated into α,β-unsaturated carbonyl compounds easily and give versatile β-amino ketones and esters in good yields. This difunctionalization reaction features mild reaction conditions, high atom-economy, and efficient access to α-SCF3 amino acids.
- Xiao, Qing,He, Qijie,Li, Juncheng,Wang, Jun
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supporting information
p. 6090 - 6093
(2016/01/09)
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- Regioselective direct C-H alkylation of NH indoles and pyrroles by a palladium/norbornene-cocatalyzed process
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Nitrogen-containing heterocycles, including 1H-indoles and electron-deficient 1H-pyrroles, undergo a palladium/norbornene-cocatalyzed regioselective alkylation at the C-H bond adjacent to the NH group. A primary alkyl halide is used as the electrophile and the reaction proceeds smoothly under mild conditions to give 2-alkyl-1H-indoles and 2-substituted or 2,3-disubstituted 5-alkyl-1H-pyrroles in good yields. Georg Thieme Verlag Stuttgart · New York.
- Jiao, Lei,Bach, Thorsten
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- CuI/Pd0 cooperative dual catalysis: Tunable stereoselective construction of tetra-substituted alkenes
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This paper describes a tunable and stereoselective dual catalytic system that uses copper and palladium reagents. This cooperative silylcupration and palladium-catalyzed allylation readily affords trisubstituted alkenylsilanes. Fine-tuning the reaction conditions allows selective access to one stereoisomer over the other. This new methodology tolerates different substituents on both coupling partners with high levels of stereoselectivity. The one-pot reaction involving a CuI/Pd0 cooperative dual catalyst directly addresses the need to develop more time-efficient and less-wasteful synthetic pathways.
- Vercruysse, Sebastien,Cornelissen, Loic,Nahra, Fady,Collard, Laurent,Riant, Olivier
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supporting information
p. 1834 - 1838
(2014/03/21)
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- Simultaneous production of biobased styrene and acrylates using ethenolysis
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Phenylalanine (1), which could be potentially obtained from biofuel waste streams, is a precursor of cinnamic acid (2) that can be converted into two bulk chemicals, styrene (3) and acrylic acid (4), via an atom efficient pathway. With 5 mol% of Hoveyda-Grubbs 2nd generation catalyst, 1 bar of ethylene, and using dichloromethane as solvent, cinnamic acid (2) can be converted to acrylic acid and styrene at 40 °C in 24 h with 13% conversion and 100% selectivity. Similar results are obtained using cinnamic acid esters (methyl, ethyl and n-butyl) as substrates and optimisation leads to higher conversions (up to 38%). For the first time, cross-metathesis of these types of electron deficient substrates was achieved.
- Spekreijse, Jurjen,Le Notre, Jerome,Scott, Elinor L.,Sanders, Johan P. M.,Van Haveren, Jacco
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supporting information
p. 2747 - 2751,5
(2020/09/14)
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- METHOD FOR SYNTHESIZING UNSATURATED CARBOXYLIC ACID AND/OR DERIVATIVE OF SAME
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An appropriate catalyst is found for synthesis of an unsaturated carboxylic acid and/or a derivative thereof using as a raw material compound a hydroxycarboxylic acid and/or a derivative thereof that can easily be synthesized from a polysaccharide such as biomass-derived cellulose, and an efficient method for synthesizing the unsaturated carboxylic acid and/or the derivative thereof is provided. This method is a method for synthesizing an unsaturated carboxylic acid and/or a derivative thereof, wherein an apatite compound is used as a catalyst to synthesize the unsaturated carboxylic acid and/or the derivative thereof from a biomass-derived hydroxycarboxylic acid and/or a derivative thereof by a dehydration reaction.
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Page/Page column 9
(2012/09/21)
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- Radical mechanism in the elimination of 2-arylsulfinyl esters
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The mechanism of the dehydrosulfenylation of 2-arylsulfinyl esters was investigated. The reaction was found to follow a homolytic cleavage mechanism as verified by electrospray ionization tandem mass spectrometry and experimental work. Rearranged sulfoxides are obtained as byproduct during the elimination reaction.
- Latorre, Antonio,Lopez, Irakusne,Ramirez, Victoria,Rodriguez, Santiago,Izquierdo, Javier,Gonzalez, Florenci V.,Vicent, Cristian
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p. 5191 - 5197
(2012/07/27)
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- Coupling reaction of magnesium alkylidene carbenoids with α-sulfonylallyllithiums: An efficient route to multi-substituted vinylallenes
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A variety of vinylallenes were successfully synthesized from 1-chlorovinyl p-tolyl sulfoxides and allyl or vinyl sulfones. Allyl and vinyl sulfones served as α-sulfonylallyllithium sources were prepared from carbonyl compounds in three or four steps in good overall yields. The coupling reaction of α-sulfonylallyllithiums with magnesium alkylidene carbenoids, which were generated from 1-chlorovinyl p-tolyl sulfoxides and isopropylmagnesium chloride, afforded multi-substituted vinylallenes in up to 88% yield. Georg Thieme Verlag KG Stuttgart · New York.
- Kimura, Tsutomu,Kobayashi, Gen,Ishigaki, Masashi,Inumaru, Mio,Sakurada, Jo,Satoh, Tsuyoshi
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p. 3623 - 3632
(2013/02/23)
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- Synthesis and biological evaluation of 3-substituted-indolin-2-one derivatives containing chloropyrrole moieties
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Eighteen novel 3-substituted-indolin-2-ones containing chloropyrroles were synthesized and their biological activities were evaluated. The presence of a chlorine atom on the pyrrole ring was crucial to reduce cardiotoxicity. The presence of a 2-(ethylamino) ethylcarbamoyl group as a substituent at the C-4' position of the pyrrole enhanced the antitumor activities notably. IC 50 values as low as 0.32, 0.67, 1.19 and 1.22 μM were achieved against non-small cell lung cancer (A549), oral epithelial (KB), melanoma (K111) and large cell lung cancer cell lines (NCI-H460), respectively.
- Jin, Yun-Zhou,Fu, Da-Xu,Ma, Nan,Li, Zhan-Cheng,Liu, Quan-Hai,Xiao, Lin,Zhang, Rong-Hua
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experimental part
p. 9368 - 9385
(2012/01/05)
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- Silver triflate-catalyzed cyclopropenation of internal alkynes with donor-/acceptor-substituted diazo compounds
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Silver triflate was found to be an efficient catalyst for the cyclopropenation of internal alkynes using donor-/acceptor-substituted diazo compounds as carbenoid precursors. Highly substituted cyclopropenes, which cannot be synthesized directly via rhodium(II)-catalyzed carbenoid chemistry, can now be readily accessed.
- Briones, John F.,Davies, Huw M. L.
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supporting information; experimental part
p. 3984 - 3987
(2011/09/16)
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- BIO-DERIVED OLEFIN SYNTHESIS
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Disclosed is a method for the combined synthesis of at least two vinylic monomers, at least one of which being an acrylic compound, comprising subjecting a monoconjgated alkene-1-carboxylic compound to reaction with a C2-C4 alkene under conditions of olefin cross-metathesis. The invention is particularly useful for extracting value from protein side streams. Upon protein hydrolysis, suitable amino acids (preferably phenylalanine or tyrosine) are subjected to reductive amination so as to form the corresponding alkene-1-carboxylic acid. Preferably after esterification and separation, this is used in cross-metathesis for the concomitant production of styrene resp. hydroxy styrene, and acrylates. The invention is applicable more widely, to the synthesis of olefins on the basis of carbohydrates, naturally occurring phenolic components, natural protein resources, or amino acids obtained from fermentations.
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Page/Page column 19
(2011/02/24)
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- POLYMERIC DRUG DELIVERY SYSTEMS AND THERMOPLASTIC EXTRUSION PROCESSES FOR PRODUCING SUCH SYSTEMS
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Implants are disclosed for delivery of therapeutic agents such as opioids and the manufacture and uses of such implants.
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- Cycloaddition of zirconacyclopentadiene with 2-bromoacrylate, 2-bromoacrylaldehyde, and 3-bromofuran-2,5-dione in the presence of cucl: A new pathway for the formation of benzene derivatives and isobenzofuran-1,3-dione
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Reaction of zirconacyclopentadienes with 2-bromoalkenes in the presence of CuCl afforded multisubstituted benzene derivatives. The reactions of 2-bromoacrylate and 2-bromo-3-phenylacrylaldehyde afforded penta-and hexasubstituted benzenes in good yields. The reaction of 3-bromofuran-2,5-dione with zirconacyclopentadienes gave isobenzofuran-1,3-diones in good yields. Copyright Taylor & Francis Group, LLC.
- Chen, Chao,Yan, Xiaoyu,Xi, Chanjuan
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experimental part
p. 570 - 579
(2010/04/06)
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- METHODS FOR THE SYNTHESIS OF OLEFINS AND DERIVATIVES
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The invention provides a method of producing acrylic acid. The method includes contacting fumaric acid with a sufficient amount of ethylene in the presence of a cross-metathesis transformation catalyst to produce about two moles of acrylic acid per mole of fumaric acid. Also provided is an acrylate ester. The method includes contacting fumarate diester with a sufficient amount of ethylene in the presence of a cross-metathesis transformation catalyst to produce about two moles of acrylate ester per mole of fumarate diester. An integrated process for process for producing acrylic acid or acrylate ester is provided which couples bioproduction of fumaric acid with metathesis transformation. An acrylic acid and an acrylate ester production also is provided.
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Page/Page column 44-47
(2009/05/29)
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- Evidence for spontaneous release of acrylates from a transition-metal complex upon coupling ethene or propene with a carboxylic moiety or CO 2
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The development of a new synthetic approach to acrylates based on the formation of alkyl esters of acrylic acids has been studied. A preformed PdCOOMe moiety is used as a model system to investigate the insertion of an olefin into the Pd-C bond. The fast elimination of acrylate is observed. Density functional calculations support the experimental findings and allow the characterization of transition states along the reaction pathway. The first example of olefin/CO2 coupling with facile release of ethyl acrylate is also presented.
- Aresta, Michele,Pastore, Carlo,Giannoccaro, Potenzo,Kovacs, Gabor,Dibenedetto, Angela,Papai, Imre
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p. 9028 - 9034
(2008/09/18)
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- A new preparation of trifluoromethanesulfinate salts
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Trifluoromethanesulfinate (triflinate) salts can be prepared in an ecofriendly way by β-elimination of aliphatic triflones bearing an acidic hydrogen in β position. This technique allows the synthesis of various triflinate salts under mild conditions.
- Langlois, Bernard R.,Billard, Thierry,Mulatier, Jean-Christophe,Yezeguelian, Catherine
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p. 851 - 856
(2008/03/13)
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- Asymmetric Diels-Alder reaction between acrylates and cyclopentadiene in the presence of chiral catalysts
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Asymmetric Diels-Alder reaction between cyclopentadiene and alkyl and cycloalkyl acrylates in the presence of new chiral catalysts, BBr 3?MentOEt, AlCl2OMent, BBr2OMent, and BBr(OMent)2, was studied. Optically active bicyclo[2.2.1]hept-2-ene- 5-carboxylates were synthesized. The influence of the reaction conditions on the total and optical yields and on the stereoselectivity of the adducts synthesized was examined. Nauka/Interperiodica 2006.
- Mamedov
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p. 1621 - 1625
(2008/02/07)
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- ZrOCl2·8H2O: An efficient, cheap and reusable catalyst for the esterification of acrylic acid and other carboxylic acids with equimolar amounts of alcohols
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Esterifications of carboxylic acids with equimolar amount of alcohols could be efficiently catalyzed by ZrOCl2·8H2O. Acrylate esters were obtained in good yields under solvent-free conditions at ambient temperature. The esterification of other carboxylic acids with alcohols also proceeded at ambient temperature or at 50°C to afford esters in high yields. If the esterification was performed in toluene under azeotropic reflux conditions to remove water, both the catalytic activity of ZrOCl 2·8H2O and the rate of esterification could be increased greatly. Furthermore, in the present catalytic system, the esters could be easily separated from the reaction mixtures and the catalyst could be easily recovered and reused.
- Sun, Hong-Bin,Hua, Ruimao,Yin, Yingwu
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p. 263 - 271
(2007/10/03)
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- Method for handling high-viscosity substances
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There is provided a method for handling high-viscosity substances discharged from a production process of acrylic acid or esters thereof by gas-phase catalytic oxidation, which method is improved such that upon transporting the high-viscosity substances in a molten state to a storage tank through a pipeline, the retention or clogging of the high-viscosity substances in the pipeline can be effectively prevented without adding a solvent thereto, resulting in smooth transportation thereof through the pipeline. In the method for handling high-viscosity substances discharged from a production process of acrylic acid or esters thereof by gas-phase catalytic oxidation according to the present invention, when the high-viscosity substances are transported to a storage tank through a pipeline, contents of acrylic acid polymers and a polymerization inhibitor in the high-viscosity substances are controlled to not less than 40% by weight and not less than 4% by weight, respectively, and the high-viscosity substances are maintained at a temperature of not less than 110° C.
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Page/Page column 5
(2008/06/13)
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- Hydrogen induced polarization-nuclear-spin hyperpolarization in catalytic hydrogenations without the enrichment of para- or orthohydrogen
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During the last 40 years, Prof. Dr. Joachim Bargon, to whom several articles in this issue are dedicated, has contributed more than 90 scientific publications to the understanding of NMR hyperpolarization phenomena such as chemically induced dynamic nucle
- Jonischkeit, Thorsten,Woelk, Klaus
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p. 960 - 969
(2007/10/03)
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- Nail varnish composition comprising at least one film-forming gradient copolymer and cosmetic process for making up and/or caring for the nails
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A nail varnish composition comprising, in a cosmetically acceptable medium, at least one film-forming gradient copolymer comprising at least two different monomeric units and exhibiting a mass polydispersity index (PI) of less than or equal to 2.5, the composition being capable of forming a film having an adhesion corresponding to a detachment percentage of less than 45%; a cosmetic process for making up and/or caring for the nails comprising the application to the nails of the cosmetic composition.
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- Fe2(SO4)3·4H 2O/concentrated H2SO4: An efficient catalyst for esterification
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The mixed catalyst system, Fe2(SO4) 3·4H2O/concentrated H2SO4 has been applied to catalyse effectively the esterification of α,β-unsaturated acids, aliphatic acids and heterocyclic aromatic acids with ethanol and methanol.
- Liang, Yong-Min,Xu, Qi-Hai,Wu, Xiao-Li,Ma, Yong-Xiang
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p. 226 - 227
(2007/10/03)
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