- Effect of palladium and copper content of zeolite catalysts on the kinetic parameters of the oxidative acetylation of propylene
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1. Using the methods of mathematical planning of an experiment, a kinetic model has been obtained for the oxidative acetylation of propylene to allyl acetate and the effect of the composition of the Pd, Cu/mordenite catalyst on its parameters has been determined. 2. The kinetic parameters (1g k0)0, Q, 1g a0 and E0 correlate strongly and form a gully on the surface of the minimized functional. Regularization of the values of the kinetic parameters was carried out by isolating a subregion of the gully satisfying the Boudart thermodynamic relationships. 3. On varying the Pd and Cu content of the catalyst within the limits 0.1 to 3.0%, the activation energy and the logarithm of the preexponential factor of the rate constant vary over the range 2-11 kcal/mole and 0.255-3.453, respectively.
- Kharlamov,Pogorelov,Panov,Yanchevskaya,Minachev
-
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Read Online
- Heterocyclization, deprotection and isomerization in an intramolecular palladium-catalysed tertiary amine-allyl coupling reaction
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N-Methyl-N-allyl-2-(1-acetoxyalIyl)benzylamine reacts in the presence of tetrakis(triphenylphosphine)palladium to afford a mixture of an isoindole, a 2-benzazepine and allyl acetate; the likely reaction pathway involves a multistep procedure whereby each Pd atom is implicated at least four times, the formation of the isoindole occuring first, followed by an isomerisation to the benzazepine derivative.
- Grellier, Mary,Pfeffer, Michel
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-
Read Online
- How to Design Selective Ligands for Highly Conserved Binding Sites: A Case Study Using N-Myristoyltransferases as a Model System
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A model system of two related enzymes with conserved binding sites, namely N-myristoyltransferase from two different organisms, was studied to decipher the driving forces that lead to selective inhibition in such cases. Using a combination of computational and experimental tools, two different selectivity-determining features were identified. For some ligands, a change in side-chain flexibility appears to be responsible for selective inhibition. Remarkably, this was observed for residues orienting their side chains away from the ligands. For other ligands, selectivity is caused by interfering with a water molecule that binds more strongly to the off-target than to the target. On the basis of this finding, a virtual screen for selective compounds was conducted, resulting in three hit compounds with the desired selectivity profile. This study delivers a guideline on how to assess selectivity-determining features in proteins with conserved binding sites and to translate this knowledge into the design of selective inhibitors.
- Kersten, Christian,Fleischer, Edmond,Kehrein, Josef,Borek, Christoph,Jaenicke, Elmar,Sotriffer, Christoph,Brenk, Ruth
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p. 2095 - 2113
(2019/09/10)
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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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- Catalytic application of zinc complex of oxygen depleted 1,3-bis(pyrazole)-p-tert-butylcalix[4]arene
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In this paper we have described the synthesis and coordination properties of monometallic Zinc complex of oxygen depleted bis(pyrazole)-p-tert-butylcalix[4]arene ligand. We also present the catalytic activity of the Zinc–bis(pyrazole) complex, in acetylation of alcohols and lactide polymerization.
- Sinha, Anshu Kumar,Vigalok, Arkadi,Rawat, Varun
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supporting information
p. 796 - 799
(2019/02/14)
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- Coating of polydopamine on polyurethane open cell foams to design soft structured supports for molecular catalysts
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Polydopamine-coated polyurethane open cell foams are used as structured supports for molecular catalysts through the covalent anchoring of alkoxysilyl arms by the catechol groups of the mussel-inspired layer. This strong bonding prevents their leaching. No alteration of the mechanical properties of the flexible support is observed after repeated uses of the catalytic materials.
- Ait Khouya, Ahmed,Mendez Martinez, Miguel L.,Bertani, Philippe,Romero, Thierry,Favier, Damien,Roland, Thierry,Guidal, Valentin,Bellière-Baca, Virginie,Edouard, David,Jierry, Lo?c,Ritleng, Vincent
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supporting information
p. 11960 - 11963
(2019/10/11)
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- METHODS AND COMPOSITIONS FOR TERPENOID SYNTHESIS
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In one aspect, the disclosure relates to methods for preparation of terpene and terpene-like molecules. In a further aspect, the disclosure relates to the products of the disclosed methods, i.e., terpene and terpene-like molecules prepared using the disclosed methods. Intermediates for the synthesis of a wide variety of terpenoids are γ-allyl Knoevenagel adducts or quasi γ-allyl Knoevenagel adducts are disclosed. In various aspects, methods of preparing terpenoids through these intermediates are disclosed. The methods can comprise α-alkylation of an allylic electrophile followed by ring-closure metathesis to a polycyclic terpenoid structure. In a further aspect, the disclosure pertains to terpenoid frameworks, and compounds prepared via disclosed oxidation and substitution reactions on the disclosed terpenoid frameworks. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
- -
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Paragraph 0090; 00140
(2018/04/13)
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- Palladium-Catalyzed Aerobic Homocoupling of Alkynes: Full Mechanistic Characterization of a More Complex Oxidase-Type Behavior
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A combined experimental and computational approach has been used to shed light on the mechanism of the Pd-catalyzed oxidative homocoupling of alkynes using oxygen as the oxidant. Mechanistic understanding is important because of the synthetically relevant direct involvement of oxygen in the oxidative coupling and because of the presence of related processes as undesired side reactions in cross-coupling reactions involving terminal alkynes. A low-ligated [Pd(PPh3)(alkyne)] complex is key in the process, and it can be conveniently generated from allylic palladium(II) complexes in the presence of a base or from Pd(I) allylic dimers as precatalysts. The catalytic coupling occurs by alkyne metalation to give an anionic [Pd(PPh3)(alkynyl)]- complex that is then oxidized by oxygen. The interaction with oxygen occurs only on this electron-rich Pd(0) anionic species and leads to a (κO,κO-peroxo)palladium(II) singlet intermediate that undergoes subsequent protonolysis to give a (κO-hydroperoxo)palladium(II) complex and then hydrogen peroxide. The second alkyne metalation occurs on a Pd(II) derivative to give a bis(alkynyl)palladium(II) complex that evolves to the product by reductive elimination as the product-forming step. This reaction is an oxidase-type process that, in contrast to most Pd-catalyzed oxidative processes, occurs without separation of the substrate transformation and the catalyst oxidation, with these two processes being intertwined and dependent on one another.
- Toledo, Alberto,Funes-Ardoiz, Ignacio,Maseras, Feliu,Albéniz, Ana C.
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p. 7495 - 7506
(2018/07/21)
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- Assembly of Terpenoid Cores by a Simple, Tunable Strategy
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Oxygenated, polycyclic terpenoid natural products have important biological activities. Although total synthesis of such terpenes is widely studied, synthetic strategies that allow for controlled placement of oxygen atoms and other functionality remains a challenge. Herein, we present a simple, scalable, and tunable synthetic strategy to assemble terpenoid-like polycycloalkanes from cycloalkanones, malononitrile, and allylic electrophiles, abundantly available reagent classes.
- Lahtigui, Ouidad,Emmetiere, Fabien,Zhang, Wei,Jirmo, Liban,Toledo-Roy, Samira,Hershberger, John C.,Macho, Jocelyn M.,Grenning, Alexander J.
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p. 15792 - 15796
(2016/12/16)
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- Method for the production of acetic acid allyl ester
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The invention relates to a method for producing propenyl ethanoate, and mainly aims at solving the problems in the prior art that a catalyst is low in activity and selectivity. Through adopting the method for producing the propenyl ethanoate, propylene, acetic acid, oxygen and water are taken as raw materials, and react with a Pd catalyst in a fixed bed reactor in a contacting manner, so as to generate an effluent containing the propenyl ethanoate; the tubular fixed bed reactor comprises at least two annular baffle plates (7) and at least one inverted conical baffle plate (8); the annular baffle plates (7) and the inverted conical baffle plate (8) are alternately arranged along the axial direction of a reaction tube (2); an upper opening and a lower opening are formed in each annular baffle plate (7); and the projection area of each upper opening in the horizontal direction is smaller than that of each lower opening in the horizontal direction. According to the technical scheme, the problem is well solved; and the method can be applied to industrial production of the propenyl ethanoate employing a propylene gas phase method.
- -
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Paragraph 0022; 0023
(2017/08/03)
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- A 2 - ((4R, 6S) - 6-substituted methyl-2-substituent -1,3-dioxane-4-yl) acetate preparation method
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The invention relates to a method for preparing 2-((4R, 6S)-6-substituted methyl-2-substituent group-1,3-dioxane-4-yl) acetate. The method comprises the following steps: by utilizing substituted ethylene and 3,3-dialkoxy propionate or 3-alkoxy acrylate, preparing 2-((4R, 6S)-6-substituted methyl-2-ester group methyl-1,3-dioxane-4-yl) acetate under catalysis of a Lewis acid; and preparing ethyl 2-((4R, 6S)-6-chloromethyl-2-substituted phenyl-1,3-dioxane-4-yl) acetate through hydrolysis ring opening and ring formation protection, performing hydrolysis ring opening again, performing ring formation protection with a carbonyl compound X or glycol XI thereof, and thus obtaining 2-((4R, 6S)-6-substituted methyl-2-substituent group-1,3-dioxane-4-yl) acetate. A chiral center is established by utilizing an equatorial bond stable form of a six-membered ring chair structure, and a chiral auxiliary reagent is not additionally used. The raw materials are readily available, the reaction process is short, asymmetric reduction of carbonyl is avoided, flammable and combustible reducing agents are not used, and the preparation method is easy, convenient, environment-friendly and suitable for large-scale industrial production.
- -
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Paragraph 0072; 0073
(2017/02/24)
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- CARBOXYLIC ACID ALLYL ESTER PRODUCTION METHOD
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PROBLEM TO BE SOLVED: To provide a production method for effectively producing carboxylic acid allyl ester used as a chemical compound industrially useful and a production raw material of various kinds of compounds industrially useful such as allyl alcohol, in which the carboxylic acid allyl ester can be produced at reaction equipment smaller and cheaper than that in a conventional gas phase condition and productivity can be improved. SOLUTION: Provided is a production method of carboxylic acid allyl ester for producing the carboxylic acid allyl ester by reacting carboxylic acid, propylene, and oxygen as raw materials, in which, in the presence of a palladium catalyst carried by a carrier, the raw materials are reacted in a liquid phase. COPYRIGHT: (C)2016,JPOandINPIT
- -
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Paragraph 0052; 0055; 0060
(2017/01/02)
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- The total chemical synthesis of the monoglycosylated GM2 ganglioside activator using a novel cysteine surrogate
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We describe a novel peptide ligation/desulfurization strategy using a β-mercapto-N-glycosylated asparagine derivative. The newly developed procedure was successfully applied to the total chemical synthesis of the GM2 ganglioside activator protein bearing a monosaccharide on the native glycosylation site.
- Sato, Kohei,Kitakaze, Keisuke,Nakamura, Takahiro,Naruse, Naoto,Aihara, Keisuke,Shigenaga, Akira,Inokuma, Tsubasa,Tsuji, Daisuke,Itoh, Kohji,Otaka, Akira
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supporting information
p. 9946 - 9948
(2015/06/22)
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- METHOD FOR PRODUCING CARBOXYLIC ACID ALLYL ESTER
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PROBLEM TO BE SOLVED: To provide a method for producing carboxylic acid allyl ester as an industrially useful chemical at a yield and a selectivity higher than those in the conventional production method. SOLUTION: Provided is a method for producing carboxylic acid allyl ester by reacting carboxylic acid, propylene and oxygen as raw materials. The production method includes: a process of reacting the raw materials in the presence of carboxylic acid anhydride using a palladium catalyst carried to a carrier. COPYRIGHT: (C)2016,JPOandINPIT
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Paragraph 0055; 0060
(2017/01/02)
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- Comparison of reactivity in the cross metathesis of allyl acetate-derivatives with oleochemical compounds
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The metathesis of unsaturated oleochemicals is an excellent tool for generating α,ω-difunctional substrates, which are useful intermediates for polymer synthesis. This article describes the cross metathesis of allyl acetate and cis-1,4-diacetoxy-2-butene with methyl 10-undecenoate and methyl oleate, which are oleochemical key substrates. Detailed optimizations led to high conversion rates and yields of the desired products under mild reaction conditions by using a low concentration of commercially available homogeneous ruthenium catalysts.
- Behr, Arno,Toepell, Stephanie
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p. 603 - 611
(2015/03/04)
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- Zinc triflate catalyzed acylation of alcohols, phenols, and thiophenols
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An expedient procedure for the acylation of alcohols, phenols, and thiophenols using catalytic amount of Zn(OTf)2 is described. This procedure is highly suitable for industrial application due to use of less toxic metal as a part of catalyst, short reaction time at ambient temperature, without any racemization of chiral alcohols.
- Kumar, N. Uday,Reddy, B. Sudhakar,Reddy, V. Prabhakar,Bandichhor, Rakeshwar
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supporting information
p. 910 - 912
(2014/02/14)
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- Zinc triflate catalyzed acylation of alcohols, phenols, and thiophenols
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An expedient procedure for the acylation of alcohols, phenols, and thiophenols using catalytic amount of Zn(OTf)2 is described. This procedure is highly suitable for industrial application due to use of less toxic metal as a part of catalyst, short reaction time at ambient temperature, without any racemization of chiral alcohols.
- Uday Kumar,Sudhakar Reddy,Prabhakar Reddy,Bandichhor, Rakeshwar
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supporting information
p. 910 - 912
(2015/02/19)
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- Vitamin B1 supported on silica-encapsulated γ-Fe 2O3 nanoparticles: Design, characterization and application as a greener biocatalyst for highly efficient acylation
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A new magnetic catalyst was synthesized by the immobilization of vitamin B1 (thiamine hydrochloride) on the surface of silica-encapsulated γ-Fe2O3 nanoparticles. Its capability was evaluated in the acylation of alcohols and phenols with acetic anhydride under solvent-free conditions and afforded the desired products in high yield. This novel magnetic organocatalyst could be separated from the reaction vessel by use of an external magnet and recovered 5 times without a significant loss of its activity. The amount of loaded vitamin B1 on the silica-encapsulated γ-Fe2O3 was assigned by TGA and confirmed by back titration. Availability, cheapness and low toxicity are reasons associated with the utilization of vitamin B1 as a catalyst. The catalyst has been characterized by FT-IR, XRD, SEM, VSM and TG/DTA. The Royal Society of Chemistry.
- Azizi, Kobra,Heydari, Akbar
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p. 8812 - 8816
(2014/03/21)
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- O2-promoted allylic acetoxylation of alkenes: Assessment of "push" versus "pull" mechanisms and comparison between O2 and benzoquinone
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Palladium-catalyzed acetoxylation of allylic C-H bonds has been the subject of extensive study. These reactions proceed via allyl-palladium(II) intermediates that react with acetate to afford the allyl acetate product. Benzoquinone and molecular oxygen are two common oxidants for these reactions. Benzoquinone has been shown to promote allyl acetate formation from well-defined π-allyl palladium(II) complexes. Here, we assess the ability of O2 to promote similar reactions with a series of "unligated" π-allyl palladium(II) complexes (i.e., in the absence of ancillary phosphorus, nitrogen or related donor ligands). Stoichiometric and catalytic allyl acetate formation is observed under aerobic conditions with several different alkenes. Mechanistic studies are most consistent with a "pull" mechanism in which O2 traps the Pd0 intermediate following reversible C-O bond formation from an allyl-palladium(II) species. A "push" mechanism, involving oxidatively induced C-O bond formation, does not appear to participate. These results and conclusions are compared with benzoquinone-promoted allylic acetoxylation, in which a "push" mechanism seems to be operative.
- Diao, Tianning,Stahl, Shannon S.
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- Efficient acetylation of alcohols and phenols catalyzed by recyclable lithium bis(perfluoroalkylsulfonyl)imide
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An efficient acetylation of alcohols and phenols catalyzed by lithium bis(perfluoroalkylsulfonyl)-imide was developed. This acetylation features good yields, mild reaction condtions, and simple workup procedures. Furthermore, the catalyst bearing a long perfluoroalkyl chain is recoverable and readily reusable without losing any activity. Copyright
- Li, Guilong,Zhao, Gang
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p. 34 - 43,10
(2020/08/24)
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- Synthesis of unsaturated esters via highly efficient esterification catalyzed by polymer grafted quarternary ammonium salts as triphase catalysts
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A series of unsaturated esters were prepared via condensation of sodium carboxylates and alkenyl halide under the condition of macroporous polystyrene grafted quarternary ammonium salt as recyclable phase transfer catalyst, NaI as co-catalyst, Cu powder as inhibitor and H2O as solvent. Under optimal conditions, products yields are 78.2~ 96.0%. The catalyst can be convenient recycled and reutilized for about five times without losing its activity obviously.
- Liang, Zheng Yong,Wang, Li Li,Liu, Hui,Huang, Jin Shuo
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p. 1558 - 1561
(2013/09/12)
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- Carbodeoxygenation of biomass: The carbonylation of glycerol and higher polyols to monocarboxylic acids
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Glycerol is converted to a mixture of butyric and isobutyric acid by rhodium- or iridium-catalysed carbonylation using HI as the co-catalyst. The initial reaction of glycerol with HI results in several intermediates that lead to isopropyl iodide, which upon carbonylation forms butyric and isobutyric acid. At low HI concentration, the intermediate allyl iodide undergoes carbonylation to give vinyl acetic acid and crotonic acid. Higher polyols CnH n+2(OH)n are carbonylated to the corresponding C n+1 mono-carboxylic acids. Copyright
- Coskun, Timur,Conifer, Christopher M.,Stevenson, Laura C.,Britovsek, George J. P.
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supporting information
p. 6840 - 6844
(2013/07/05)
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- Efficient allylation of nucleophiles catalyzed by a bifunctional heterogeneous palladium complex-tertiary amine system
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We demonstrate the synergistic catalysis of a silica-supported diaminopalladium complex and a tertiary amine (SiO2/diamine/Pd/ NEt2) as well as synthetic scope of the Tsuji-Trost reaction of 1,3-dicarbonyls, phenols, and carboxylic acids with allyl carbonate and acetates. The synergistic catalysis of SiO2/diamine/Pd/NEt 2 exhibited wide applicability and high activity for the Tsuji-Trost reaction. For example, the reaction of ethyl 3-oxobutanate with allyl methyl carbonate afforded the allylated product in >99% yield at 70 °C for 5 h. The yield of allylated products was 26% for SiO2/diamine/Pd, without immobilization of the tertiary amine group. In the reaction of 1.0 mmol of ethyl 3-oxobutanate using 0.60 μmol of Pd in SiO2/diamine/Pd/NEt 2, the turnover number (TON) of Pd reached up to 1070 within 24 h. Phenols with electron-withdrawing groups, such as nitro and chloro groups, on the para position resulted in high product yields. The SiO2/diamine/ Pd/NEt2 catalyst was reusable at least 4 times without appreciable loss of its activity and selectivity in the reaction of p-chlorophenol. Copyright
- Noda, Hiroto,Motokura, Ken,Miyaji, Akimitsu,Baba, Toshihide
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p. 973 - 980
(2013/05/08)
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- Hoveyda-Grubbs first generation type catalyst immobilized on mesoporous molecular sieves
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New heterogeneous, reusable catalysts for olefin metathesis have been prepared by immobilizing the Hoveyda-Grubbs first generation type alkylidene (commercially available as the Zhan catalyst-1C) on siliceous mesoporous molecular sieves with different pore sizes and architectures (SBA-15, SBA-16, MCM-41 and MCM-48) having the surface modified with molecules bearing dicyclohexylphosphine (PCy2) end groups. Resulting novel heterogenized catalysts proved high activity in ring-closing metathesis (RCM) of 1,7-octadiene, diethyl diallylmalonate, tert-butyl N,N-diallylcarbamate and N,N-diallyl-2,2,2-trifluoroacetamide, in homometathesis of 1-decene, 5-hexenyl acetate and methyl 10-undecenoate, and in cross-metathesis (CM) of allylbenzene with cis-1,4-diacetoxy-2-butene. The catalytic activity decreased with decreasing pore size of supports in the order SBA-15 > MCM-48 > SBA-16 and MCM-41. Filtration test suggested that the solid catalyst was responsible for the catalytic activity. Catalysts were easily separated from the reaction mixtures and products of low levels of Ru concentration were obtained.
- Pastva, Jakub,?ejka, Ji?í,?ilková, Nadě?da,Mestek, Oto,Rangus, Mojca,Balcar, Hynek
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p. 184 - 192
(2013/08/23)
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- Polystyrene-supported GaCl3: A new, highly efficient and recyclable heterogeneous Lewis acid catalyst for acetylation and benzoylation of alcohols and phenols
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A new, simple and highly chemoselective method for both acetylation and benzoylation of alcohols and phenols with acetic anhydride in the presence of polystyrene-supported gallium trichloride (PS/GaCl3) as a highly active and reusable heterogeneous Lewis acid catalyst is presented. In this catalytic system, primary, secondary and tertiary alcohols as well as phenols were converted to the corresponding acetates and benzoates with high yields. The heterogenized catalyst is of high reusability and stability in the acetylation reactions and was recovered several times with negligible loss in its activity or a negligible catalyst leaching, and also there is no need for regeneration. Remarkably, a selective mono-acetylation of symmetrical diols can be achieved chemoselectively by employing the same catalyst.
- Rahmatpour, Ali
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p. 1048 - 1054
(2013/02/22)
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- PROCESS FOR PRODUCTION OF ALLYL ACETATE
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Disclosed is a process for production of allyl acetate, which comprises steps of reacting acetic acid 3, oxygen 1 and propylene 2 in the presence of a catalyst in an oxidation reactor 5 to form allyl acetate and water; separating the unreacted acetic acid by a distillation column 9; and recovering an acetic acid- containing liquid which contains acetic acid and returning the acetic acid- containing liquid to the oxidation reactor 5 via an acetic acid-water evaporator 4, the process further including a heating step of heating a process liquid which contains the acetic acid- containing liquid to a temperature of 80 to 250 °C by a heater.
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Page/Page column 42-49; 53
(2012/04/10)
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- Investigation of steapsin lipase for kinetic resolution of secondary alcohols and synthesis of valuable acetates in non-aqueous reaction medium
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In present study, the application of steapsin lipase (as a biocatalyst) was investigated for kinetic resolution of secondary alcohols (1-phenyl ethanol and their derivatives) using vinyl acetate as an activated acyl donor. The enzymatic protocol was optimized for various reaction parameters such as effect of the molar ratio, solvent, temperature, time and biocatalyst loading to obtain best reaction conditions. On optimization, developed enzymatic methodology provided considerable enantiomeric excess of the product (up to 92% ee) at 55 °C in n-hexane as a solvent. Furthermore using the developed protocol, synthesis of several industrially important acetates was successfully achieved with excellent yield (up to 99%). During acetate synthesis, the biocatalyst was remarkably reused for eight consecutive recycles without any significant loss in its catalytic activity. This revealed the good potential of steapsin lipase for application in organic solvents.
- Dhake, Kishor P.,Deshmukh, Krishna M.,Wagh, Yogesh S.,Singhal, Rekha S.,Bhanage, Bhalchandra M.
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experimental part
p. 15 - 23
(2012/06/29)
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- Photoswitchable organocatalysis: Using light to modulate the catalytic activities of N-heterocyclic carbenes
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A 4,5-dithienylimidazolium salt was found to undergo electrocyclic isomerization upon exposure to UV radiation (λirr = 313 nm) under neutral and basic conditions; subsequent exposure to visible light reversed the reaction. Under ambient light and in the presence of base, the imidazolium species catalyzed transesterifications as well as amidations in a manner similar to those of previously reported N-heterocyclic carbene precatalysts. However, upon UV irradiation to effect the aforementioned photocyclization, the rate of the transesterification reaction between vinyl acetate and allyl alcohol was significantly attenuated (kvis/UV = 12.5), as was the rate of the condensation of ethyl acetate with aminoethanol (kvis/UV = 100). The rates of these reactions were successfully toggled between fast and slow states by alternating exposure to visible and UV light, respectively, thus demonstrating a rare example of a photoswitchable catalyst that operates via photomodulation of its electronic structure.
- Neilson, Bethany M.,Bielawski, Christopher W.
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supporting information; experimental part
p. 12693 - 12699
(2012/09/05)
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- Ruthenium metathesis catalyst bearing chelating carboxylate ligand immobilized on mesoporous molecular sieve SBA-15
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Ruthenium complex 3b bearing chelating carboxylate ligand was immobilized on mesoporous molecular sieve SBA-15 via cleavage of carboxylate by fluorocarboxylic acid groups introduced on the support surface. The hybrid olefin metathesis catalyst Ru/L/SBA-15, prepared straightforward without use of silver salts, exhibited high activity and selectivity in model metathesis reactions and low ruthenium leaching.
- Bek, David,Gawin, Rafa?,Grela, Karol,Balcar, Hynek
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scheme or table
p. 42 - 45
(2012/06/01)
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- Task-oriented use of ionic liquids: Efficient acetylation of alcohols and phenols
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The ionic liquid 1-butyl-3-methylimidazolium acetate proves to be an excellent reaction medium for the acetylation of alcohols and phenols, providing better conditions than the acidic 1-butyl-3-methylimidazolium bisulfate. Reactions were carried at room temperature, with only a 10% excess of acylating agent and with no other solvent or catalyst added.
- López, Ignacio,Bravo, José Luis,Caraballo, Manuel,Barneto, José Luis,Silvero, Guadalupe
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scheme or table
p. 3339 - 3341
(2011/06/28)
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- Iron (III) phosphate as a green and reusable catalyst promoted chemo selective acetylation of alcohols and phenols with acetic anhydride under solvent free conditions at room temperature
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Iron (III) phosphate was employed as an efficient catalyst for the chemo selective acetylation of alcohols and phenols under solvent free condition at room temperature and with high yields. Iron (III) phosphate is also a potential green catalyst due to solid intrinsically, reusable and with high catalytic activity.
- Behbahani,Farahani,Oskooie
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experimental part
p. 633 - 637
(2011/10/08)
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- Cobalt-catalyzed reductive allylation of alkyl halides with allylic acetates or carbonates
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An efficient method for the direct allylation of alkyl halides catalyzed by simple cobalt(II) bromide has been developed. This reaction, using a variety of substituted allylic acetates or carbonates, provides the linear product as the major product. It displays broad substrate scope and good functional group tolerance. Copyright
- Qian, Xin,Auffrant, Audrey,Felouat, Abdellah,Gosmini, Corinne
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supporting information; experimental part
p. 10402 - 10405
(2011/12/03)
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- Process for producing allyl acetate
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A process for producing allyl acetate is disclosed. The process comprises reacting a feed comprising propylene, acetic acid, oxygen, and carbon dioxide in the presence of a supported palladium catalyst. The feed comprises from 2 to 6 mole percent carbon dioxide, which improves the selectivity to allyl acetate.
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Page/Page column 3-4
(2011/04/19)
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- METHOD FOR PRODUCING N-PROPYL ACETATE AND METHOD FOR PRODUCING ALLYL ACETATE
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Provided is a method for producing n-propyl acetate, which is capable of obtaining high-purity allyl acetate with a low amount of coexisting water and is capable of producing n-propyl acetate with a high yield. The method includes an extraction process of subjecting a raw material liquid containing allyl acetate and water to an extraction operation using water as an extraction solvent and separating the extract into an oily phase and an aqueous phase, a distillation process of distilling the oily phase to obtain a distillate containing allyl acetate as a main component, and a hydrogenation process of subjecting the distillate to a hydrogenation reaction.
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Page/Page column 40-42
(2011/10/13)
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- Process for producing allyl alcohol
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A process for producing allyl alcohol is disclosed. The process comprises reacting propylene, acetic acid, and oxygen to produce a reaction mixture. The reaction mixture is distilled to produce a vapor stream comprising propylene and a liquid stream comprising allyl acetate, acetic acid, acrolein, and allyl diacetate. The liquid stream is distilled to produce a lights stream comprising acrolein; a side draw comprising allyl acetate, acetic acid, and water; and a bottoms stream comprising acetic acid and allyl diacetate. The bottoms stream is distilled to remove a heavies stream comprising allyl diacetate. The side draw is hydrolyzed to produce allyl alcohol.
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Page/Page column 3-4
(2011/09/16)
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- Allylic C-H acetoxylation with a 4,5-diazafluorenone-ligated palladium catalyst: A ligand-based strategy to achieve aerobic catalytic turnover
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Pd-catalyzed C-H oxidation reactions often require the use of oxidants other than O2. Here we demonstrate a ligand-based strategy to replace benzoquinone with O2 as the stoichiometric oxidant in Pd-catalyzed allylic C-H acetoxylation. Use of 4,5-diazafluorenone (1) as an ancillary ligand for Pd(OAc)2 enables terminal alkenes to be converted to linear allylic acetoxylation products in good yields and selectivity under 1 atm O 2. Mechanistic studies have revealed that 1 facilitates C-O reductive elimination from a π-allyl-PdII intermediate, thereby eliminating the requirement for benzoquinone in this key catalytic step.
- Campbell, Alison N.,White, Paul B.,Guzei, Ilia A.,Stahl, Shannon S.
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supporting information; experimental part
p. 15116 - 15119
(2011/01/06)
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- PROCESS FOR PRODUCTION OF ALLYL ACETATE PRODUCTION CATALYST
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An allyl acetate production catalyst comprising at least (a) palladium, (b) gold, (c) a compound containing at least one element selected from copper, nickel, zinc and cobalt, (d) an alkali metal salt compound and (e) a carrier, is produced by a process comprising step 1 in which a homogeneous solution of a palladium-containing compound and a gold-containing compound is supported on a carrier by contact therewith, step 2 in which the carrier obtained in step 1 is contacted with an alkali solution for impregnation, step 3 in which the carrier obtained in step 2 is subjected to reduction treatment, and step 4 in which a compound containing at least one element selected from copper, nickel, zinc and cobalt and an alkali metal salt compound are supported onto the carrier obtained in step 3. The obtained allyl acetate production catalyst has minimal reduction in activity and improved selectivity, when used for production of allyl acetate from propylene, oxygen and acetic acid.
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- Mechanistic investigations of bipyrimidine-promoted palladium-catalyzed allylic acetoxylation of olefins
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Several pyridine-like ligands were found to improve Pd(OAc) 2-catalyzed allylic oxidation of allylbenzene to cinnamyl acetate by p-benzoquinone in acetic acid. The best ligand examined, bipyrimidine, was used to identify the catalyst precursor for this system, (bipyrimidine)Pd(OAc) 2, which was fully characterized. Mechanistic studies suggest the reaction takes place through disproportionation of (bipyrimidine)Pd(OAc) 2 to form a bipyrimidine-bridged dimer, which reacts with olefin to form a PdII-olefin adduct, followed by allylic C-H activation to produce (η3-allyl)PdII species. The (η3-allyl)PdII intermediate undergoes a reversible acetate attack to generate a Pd0-(allyl acetate) adduct, which subsequently reacts with p-benzoquinone to release allyl acetate and regenerate (bipyrimidine)Pd(OAc)2. No KIE is observed for the competition experiment between allylbenzene-d0 and allylbenzene-d5 (CD2=CDCD2C6H5), suggesting that allylic C-H activation is not rate-determining. Catalytic allylic acetoxylations of other terminal olefins as well as cyclohexene were also effected by (bipyrimidine)Pd(OAc)2.
- Lin, Bo-Lin,Labinger, Jay A.,Bercaw, John E.
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experimental part
p. 264 - 271
(2009/10/23)
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- Synthesis of methacrylate-functionalized phosphonates and phosphates with long alkyl-chain spacers and their self-aggregation in aqueous solutions
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Polymerizable amphiphilic organophosphorous compounds were synthesized and their self-aggregation behavior was investigated. The studied molecules contain a hydrophilic phosphorus end group, an alkyl chain spacer with a variable length from 3 to 11 CH2 groups and a polymerizable methacrylic group at the other chain end. Thus, the molecules represent a class of polymerizable surfactants. Two different reaction methods were used; either unsaturated alcohols or bromine-containing alcohols were applied as starting compounds for the preparation of the organophosphorous surfactants. The self-aggregation and micelle formation of the prepared compounds were investigated in aqueous solution by dynamic light scattering measurements. The critical micelle concentration of the P-containing amphiphiles was in all cases smaller than 0.040 mol/l and strongly dependent on the polarity of the phorphorous head group and the chain length of the spacer. Graphical abstract: [Figure not available: see fulltext.] The synthesis of organophosphorous amphiphiles as surface active monomers for the modification of metal oxide surfaces is presented. The spacer between the phosphorous head group and the methacrylate group was varied with regard to their length and composition. The self-aggregation behavior of these methacrylate-functionalized phosphates and phosphonates surfactants was investigated.
- Francova, Denisa,Kickelbick, Guido
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experimental part
p. 413 - 422
(2010/06/14)
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- Vanadyl sulfate (VOSO4.3H2O). An efficient catalyst for acylation of alcohols and phenols under solvent free condition
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Alcohols and phenols were efficiently acylated with acetic anhydride in the presence of vanadyl sulfate (VOSO4.3H2O) at room temperature in high yields.
- Oskooie, Hossein A.,Baghernezhad, Bita,Heravi, Majid M.,Beheshtiha
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experimental part
p. 713 - 715
(2009/12/03)
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- Copper triflate/t-BuOOAc-catalyzed amidation of allylic and benzylic acetates with sulfonamides
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A copper triflate/t-BuOOAc-catalyzed amidation of allylic and benzylic acetates has been developed which is suitable for the coupling of a wide variety of functionalized sulfonamide nucleophiles with acetate electrophiles. The methodology allows for the amidation of benzylic substrates which are not further activated by an additional adjacent alkene or alkyne, enabling simple allylic acetates and primary benzylic acetates to be used as reaction partners.
- Powell, David A.,Pelletier, Guillaume
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p. 2495 - 2498
(2008/09/19)
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- A novel one-pot conversion of allyl alcohols into primary allyl halides mediated by acetyl halide
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A new and simple method for the synthesis of the primary allyl chlorides and bromides 9-16 from the secondary or tertiary allyl alcohols 3-8 and acyl halide was developed (Scheme 2, Table 1). Non-commercially available secondary and tertiary allyl alcohols were synthesized from the related ketones and aldehydes via the addition of vinylmagnesium chloride. Mechanistic studies indicate that the alcohols were first acetylated by the acetyl halide and then protonated prior to substitution by the halide, Cl- or Br -, via an 5N2′ reaction, to yield the primary halides (Scheme 5).
- Kishali, Nurhan,Polat, M. Fatih,Altundas, Ramazan,Kara, Yunus
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- Ruthenium(III) acetylacetonate [Ru(acac)3] -An efficient recyclable catalyst for the acetylation of phenols, alcohols, and amines under neat conditions
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A catalytic amount of ruthenium(III) acetylacetonate (2 mol%) [Ru(acac)3] enables solvent-free acetylation of phenols, alcohols, and amines at ambient temperature in good to excellent yields. Furthermore, the catalyst could be recovered and reused at least three times without a significant loss in yields.
- Varala, Ravi,Nasreen, Aayesha,Adapa, Srinivas R.
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p. 148 - 152
(2008/02/11)
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- Selective acetylation of alcohols and amines with ethyl acetate in the presence of H6[PMo9V3O40] as the catalyst
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Acetylation of various alcohols and benzyl amine was tested in the presence of H6[PMo9V3O40], a mixed addenda heteropolyacid, in ethyl acetate under reflux condition. Phenols and anilines are not affected under the reaction conditions. Selective transestrification of alcohols can be achieved in the presence of phenol and aniline derivatives using this method. Springer-Verlag 2007.
- Heravi, Majid M.,Bakhtiari, Khadijeh,Javadi, Negar M.,Oskooie, Hossein A.,Bamoharram, Fatemeh F.
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p. 445 - 447
(2008/02/02)
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- An improved synthesis of morpholino-glycoamino acids
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The current synthesis of hybrid morpholino-glycoamino acids through double reductive amination is characterized by modest yields and lengthy reaction times. We propose an optimized procedure that results in improved yields and the shortest reaction times reported so far.
- Anderluh, Marko
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p. 9203 - 9206
(2007/10/03)
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- Practical preparation of esters and thioacetates from alkyl halides and carboxylates or thioacetate catalyzed by PEG400 without solvent
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Carboxylic esters and thioacetates were conveniently prepared in good to excellent yields under mild conditions by the reaction of alkyl halides with sodium carboxylates or sodium thioacetate catalyzed by PEG400 in the absence of solvents. Copyright Taylor & Francis Group, LLC.
- Cao, Yu-Qing,Wu, Guo-Qiang,Li, Ya-Bin,Dai, Zhi,Chen, Bao-Hua
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p. 3353 - 3358
(2007/10/03)
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- A green protocol for chemoselective O-acylation in the presence of zinc oxide as a heterogeneous, reusable and eco-friendly catalyst
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The solvent-free acylation of alcohols and phenols with acyl chlorides using ZnO as a catalyst is described. The remarkable selectivity under mild and neutral conditions, and recyclability of the catalyst, are advantages.
- Tamaddon, Fatemeh,Amrollahi, Mohammad Ali,Sharafat, Leily
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p. 7841 - 7844
(2007/10/03)
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- Facile catalyzed acylation of alcohols, phenols, amines and thiols based on ZrOCl2·8H2O and acetyl chloride in solution and in solvent-free conditions
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Acylation of heteroatoms (O, N and S) with acetyl chloride based on the use of a catalytic amount of the moisture stable, inexpensive ZrOCl 2?8H2O, proceeds efficiently producing the corresponding acylated products in excellent yields.
- Ghosh, Rina,Maiti, Swarupananda,Chakraborty, Arijit
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p. 147 - 151
(2007/10/03)
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- Zinc oxide (ZnO) as a new, highly efficient, and reusable catalyst for acylation of alcohols, phenols and amines under solvent free conditions
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Zinc oxide (ZnO) is a highly efficient catalyst for the acylation of a variety of alcohols, phenols and amines with acid chlorides or acid anhydrides under solvent free conditions. Primary, secondary, tertiary, allylic and benzylic alcohols, diols and phenols with electron donating or withdrawing substituents can be easily acylated in good to excellent yield.
- Hosseini Sarvari, Mona,Sharghi, Hashem
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p. 10903 - 10907
(2007/10/03)
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- Silphos [PCl3-n(SiO2)n]: A heterogeneous phosphine reagent for formylation and acetylation of alcohols and amines with ethyl formate and acetate
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Alcohols and amines are formylated and acetylated in the presence of Silphos [PCl3-n(SiO2)n] in ethyl formate and ethyl acetate in high to excellent yields. This procedure provides a method to separate the product by a simple filtration.
- Iranpoor, Nasser,Firouzabadi, Habib,Jamalian, Arezu
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p. 7963 - 7966
(2007/10/03)
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- PRODUCTION PROCESSES OF LOWER ALIPHATIC CARBOXYLIC ACID ALKENYL ESTERS AND ALKENYL ALCOHOL
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A process for producing a lower aliphatic carboxylic acid alkenyl, comprising reacting a lower olefin, a lower aliphatic carboxylic acid and oxygen in a gas phase in the presence of a catalyst comprising a support having supported thereon a catalyst component containing a compound containing alkali metal and/or alkaline earth metal, an element belonging to Group 11 of the Periodic Table or a compound containing at least one of these elements, and palladium, wherein the outflow ratio of the compound containing alkali metal and/or alkaline earth metal is from 1.0(10-5 to 0.01%/h.
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Page 23-25; 26-29
(2008/06/13)
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