- Depolymerization of Hydroxylated Polymers via Light-Driven C-C Bond Cleavage
-
The accumulation of persistent plastic waste in the environment is widely recognized as an ecological crisis. New chemical technologies are necessary both to recycle existing plastic waste streams into high-value chemical feedstocks and to develop next-generation materials that are degradable by design. Here, we report a catalytic methodology for the depolymerization of a commercial phenoxy resin and high molecular weight hydroxylated polyolefin derivatives upon visible light irradiation near ambient temperature. Proton-coupled electron transfer (PCET) activation of hydroxyl groups periodically spaced along the polymer backbone furnishes reactive alkoxy radicals that promote chain fragmentation through C-C bond β-scission. The depolymerization produces well-defined and isolable product mixtures that are readily diversified to polycondensation monomers. In addition to controlling depolymerization, the hydroxyl group modulates the thermomechanical properties of these polyolefin derivatives, yielding materials with diverse properties. These results demonstrate a new approach to polymer recycling based on light-driven C-C bond cleavage that has the potential to establish new links within a circular polymer economy and influence the development of new degradable-by-design polyolefin materials.
- Nguyen, Suong T.,McLoughlin, Elizabeth A.,Cox, James H.,Fors, Brett P.,Knowles, Robert R.
-
p. 12268 - 12277
(2021/08/23)
-
- A direct synthesis of carboxylic acidsviaplatinum-catalysed hydroxycarbonylation of olefins
-
The platinum-catalysed hydroxycarbonylation of olefins is reported for the first time. Using a combination of PtCl2/2,2′-bis(tert-butyl(pyridin-2-yl)phosphanyl)-1,1′-binaphthalene (Neolephos) in the presence of sulfuric acid [0.6 M] in acetic acid selective carbonylation of terminal aliphatic olefins proceeds to good yields and selectivities to the corresponding carboxylic acids. Comparing the reactivity of different butenes (iso- andn-butenes), the terminal olefin can be selectively carbonylated.
- Schneider, Carolin,Franke, Robert,Jackstell, Ralf,Beller, Matthias
-
p. 2703 - 2707
(2021/05/05)
-
- Synthesis of Dicarboxylic Acids from Aqueous Solutions of Diols with Hydrogen Evolution Catalyzed by an Iridium Complex
-
A catalytic system for the synthesis of dicarboxylic acids from aqueous solutions of diols accompanied by the evolution of hydrogen was developed. An iridium complex bearing a functional bipyridonate ligand with N,N-dimethylamino substituents exhibited a high catalytic performance for this type of dehydrogenative reaction. For example, adipic acid was synthesized from an aqueous solution of 1,6-hexanediol in 97 % yield accompanied by the evolution of four equivalents of hydrogen by the present catalytic system. It should be noted that the simultaneous production of industrially important dicarboxylic acids and hydrogen, which is useful as an energy carrier, was achieved. In addition, the selective dehydrogenative oxidation of vicinal diols to give α-hydroxycarboxylic acids was also accomplished.
- Fujita, Ken-ichi,Toyooka, Genki
-
-
- A mild reaction conditions of the catalytic oxidation of cyclooctane new method (by machine translation)
-
A cyclooctane catalytic oxidation method, said method comprising: the metal porphyrin, cyclooctane mixing, at a temperature of 80 - 120 °C, O2 The pressure 0.6 - 2 mpa reaction under the condition of 2 - 48 H-, after processing reaction liquid, separating the oxidation product [...], cyclooctanol, ring octanone; the invention relates to a new method of cyclooctane catalytic oxidation reaction temperature is low, the catalyst amount is less, but in order to O2 As the oxidizing agent, environmental protection, cyclooctane can be the highly selective oxide cyclooctanol, ring octanone and [...], the catalytic oxidation of cyclooctane new method also has the simple operation, does not use an organic solvent, ring octanone selectivity and the like. (by machine translation)
- -
-
Paragraph 0017-0018; 0021-0022; 0031-0032
(2019/03/28)
-
- Colloidal tectonics for tandem synergistic Pickering interfacial catalysis: Oxidative cleavage of cyclohexene oxide into adipic acid
-
Supramolecular preorganization and interfacial recognition can provide useful architectures for colloidal building. To this aim, a novel approach, based on colloidal tectonics involving two surface-active particles containing both recognition and catalytic sites, has been developed for controlling the formation and the properties of Pickering emulsions. This was illustrated by the combination of dodecyltrimethylammonium phosphotungstate nanoparticles, [C12]3[PW12O40], and silica particles functionalized with alkyl and sulfonic acid groups, [Cn/SO3H]@SiO2. The interfacial self-assembly occurs by the penetration of the alkyl chains of [Cn/SO3H]@SiO2 into the [C12]3[PW12O40] supramolecular porous structure constituted of polar and apolar regions. The emulsions were used as a non-nitric acid route for adipic acid synthesis from the one-pot oxidative cleavage of cyclohexene oxide with aqueous H2O2. The catalytic performance was significantly boosted due to the synergistic interactions between the particles.
- Yang, Bingyu,Leclercq, Lo?c,Schmitt, Véronique,Pera-Titus, Marc,Nardello-Rataj, Véronique
-
p. 501 - 507
(2019/01/10)
-
- Metal-Free Synthesis of Adipic Acid via Organocatalytic Direct Oxidation of Cyclohexane under Ambient Temperature and Pressure
-
A direct metal-free approach for the production of adipic acid from cyclohexane is reported. The use of N-hydroxyphthalimide (NHPI) as a catalyst in the presence of HNO3/TFA enables the direct oxidation of cyclohexane to yield adipic acid under ambient temperature and pressure via a simple procedure. This reaction proceeds through an initial oxidation of cyclohexane to cyclohexanone oxime and cyclohexanone followed by a second oxidation of these intermediates to adipic acid. NHPI plays a crucial role in both oxidation steps to achieve a high yield and selectivity for adipic acid.
- Matsumoto, Yohei,Kuriyama, Masami,Yamamoto, Kosuke,Nishida, Koyo,Onomura, Osamu
-
supporting information
p. 1312 - 1317
(2018/09/25)
-
- Silver(I)-Catalyzed Widely Applicable Aerobic 1,2-Diol Oxidative Cleavage
-
The oxidative cleavage of 1,2-diols is a fundamental organic transformation. The stoichiometric oxidants that are still predominantly used for such oxidative cleavage, such as H5IO6, Pb(OAc)4, and KMnO4, generate stoichiometric hazardous waste. Herein, we describe a widely applicable and highly selective silver(I)-catalyzed oxidative cleavage of 1,2-diols that consumes atmospheric oxygen as the sole oxidant, thus serving as a potentially greener alternative to the classical transformations.
- Zhou, Zhong-Zhen,Liu, Mingxin,Lv, Leiyang,Li, Chao-Jun
-
supporting information
p. 2616 - 2620
(2018/02/13)
-
- Highly efficient oxidative cleavage of alkenes and cyanosilylation of aldehydes catalysed by magnetically recoverable MIL-101
-
The catalytic activity of magnetically recoverable MIL-101 was investigated in the oxidation of alkenes to carboxylic acids and cyanosilylation of aldehydes. MIL-101 was treated with Fe3O4 and the prepared catalyst was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, N2 adsorption measurements, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and inductively coupled plasma analysis. The catalytic active sites in this heterogeneous catalyst are Cr3+ nodes of the MIL-101 framework. This heterogeneous catalyst has the advantages of excellent yields, short reaction times and reusability several times without significant decrease in its initial activity and stability in both oxidation and cyanosilylation reactions. Its magnetic property allows its easy separation using an external magnetic field.
- Nourian, Maryam,Zadehahmadi, Farnaz,Kardanpour, Reihaneh,Tangestaninejad, Shahram,Moghadam, Majid,Mirkhani, Valiollah,Mohammadpoor-Baltork, Iraj
-
-
- The aliphatic dicarboxylic acid compound (by machine translation)
-
PROBLEM TO BE SOLVED: To obtain an aliphatic dicarboxylic acid compound industrially useful as a monomer for high molecular compounds in a high yield and good selectivity under mild conditions.SOLUTION: An aliphatic cyclic hydrocarbon compound such as cyclohexane is efficiently oxidized into an aliphatic dicarboxylic acid compound by oxidizing the aliphatic cyclic hydrocarbon compound with nitric acid or a nitrate, in the presence of trifluoroacetic acid and an N-hydroxyimide compound. When an aliphatic cyclic hydrocarbon compound having a symmetric structure is adopted as a raw material, the obtained aliphatic dicarboxylic acid compound is single.
- -
-
Paragraph 0040; 0049; 0050
(2017/08/02)
-
- MIXED OXIDES FOR THE OXIDATIVE CLEAVAGE OF LIPIDS USING OXYGEN TO AFFORD MONO- AND DI-CARBOXYLIC ACIDS
-
This invention relates to the synthesis of new catalysts based on earth crust abundant mixed oxides that can produce cleavage of fatty acids (FA), FA methyl esters, or even lipids in a single step using oxygen as oxidant in solventless conditions.
- -
-
Page/Page column 10-11
(2017/12/29)
-
- Cp? versus Bis-carbonyl iridium precursors as CH oxidation precatalysts
-
We previously reported a dimeric IrIV-oxo species as the active water oxidation catalyst formed from a Cp?Ir(pyalc)Cl {pyalc = 2-(2′-pyridyl)-2-propanoate} precursor, where the Cp? is lost to oxidative degradation during catalyst activation; this system can also oxidize unactivated CH bonds. We now show that the same Cp?Ir(pyalc)Cl precursor leads to two distinct active catalysts for CH oxidation. In the presence of external CH substrate, the Cp? remains ligated to the Ir center during catalysis; the active species-likely a highvalent Cp?Ir(pyalc) species-will oxidize the substrate instead of its own Cp?. If there is no external CH substrate in the reaction mixture, the Cp? will be oxidized and lost, and the active species is then an iridium-μ-oxo dimer. Additionally, the recently reported Ir(CO)2(pyalc) water oxidation precatalyst is now found to be an efficient, stereoretentive CH oxidation precursor. We compare the reactivity of Ir(CO)2(pyalc) and Cp?Ir(pyalc)Cl precursors and show that both can lose their placeholder ligands, CO or Cp?, to form substantially similar dimeric IrIV-oxo catalyst resting states. The more efficient activation of the bis-carbonyl precursor makes it less inhibited by obligatory byproducts formed from Cp? degradation, and therefore the dicarbonyl is our preferred precatalyst for oxidation catalysis.
- Huang, Daria L.,Vinyard, David J.,Blakemore, James D.,Hashmi, Sara M.,Crabtree, Robert H.
-
p. 199 - 206
(2017/11/27)
-
- Method for preparing acid through oxidating alcohols or aldehydes by oxygen
-
The invention provides a method for preparing acid through oxidating alcohols or aldehydes by using oxygen or oxygen in air as an oxidant. The method comprises the steps: oxidating the alcohols or aldehydes to produce the acid at room temperature in an organic solvent in a manner of taking ferric nitrate (Fe(NO3)3.9H2O), 2,2,6,6-tetramethylpiperidyl nitrogen oxide (TEMPO) and an inorganic halide as catalysts and taking the oxygen or air as an oxidant, and oxidating diols to produce lactone; or, carrying out a reaction on the aldehydes, which serve as a raw material, under neutral conditions by taking ferric nitrate as a catalyst, and oxidating the aldehydes to produce the acid and peroxy acid. The method has the advantages that the method is environmentally friendly, the cost is low, the yield is high, the atomic economical efficiency is high, the compatibility of substrate functional groups is good, the reaction conditions are mild, a reaction scale can be enlarged, and the like, so that the method is suitable for being applied to industrial production.
- -
-
Paragraph 0051; 0052; 0053; 0054; 0094; 0095; 0096-0099
(2017/09/29)
-
- Preparation and characterization of WO3 bonded imidazolium sulfonic acid chloride as a novel and green ionic liquid catalyst for the synthesis of adipic acid
-
A novel nano WO3-bonded imidazolium-sulfonic acid chloride (WO3-IL) was prepared, and characterized by FT-IR, XRD, SEM, TEM, EDX and BET. The as synthesized WO3 nanoparticle supported ionic liquid is studied as a heterogeneous catalyst for the liquid phase oxidation of cyclohexene to adipic acid. Apart from cyclohexene, a few other six-eight membered cyclic alcohols and ketones are converted into their dicarboxylic acids in high yields and in short reaction times employing the same reaction protocol. The synergy between the WO3 and ionic liquid is assumed to play a significant role towards its very high catalytic activity. The recyclability of the catalyst is proved to be noteworthy as the catalyst exhibits no significant change in its catalytic activity even after five cycles of reuse.
- Bhuyan, Bishal,Paul, Bappi,Vadivel, Sethumathavan,Dhar, Siddhartha Sankar
-
p. 99044 - 99052
(2016/11/02)
-
- Molybdenum Complexes as Catalysts for the Oxidation of Cycloalkanes with Molecular Oxygen
-
A group of new polymolybdates was synthesized and tested in the catalytic oxidation of cycloalkanes. Investigated compounds exhibit broad structural diversity including polymolybdates with isolated anionic clusters (0-dim), polymeric anions (1-dim), Mo-O layers (2-dim) as well as hexagonal and orthorhombic molybdenum oxides (3-dim). All studied molybdenum complexes were found to be active in the reaction conditions yielding ketones and alcohols as main products. In the case of layered compounds (2-dim), dicarboxylic acid was detected in the mixture of reaction products. The structure of investigated molybdenum compounds was shown to have influence on yields and selectivities of the investigated reactions. Anionic layers separation (in 2-dim materials) as well as type and charge of organic cations present in the compounds are prime examples of structural factors influencing the oxidation reactions efficiencies. On the basis of obtained results and literature reports a mechanism for the oxidation of cycloalkanes by polymolybdates has been proposed.
- Szymańska, Anna,Nitek, Wojciech,Oszajca, Marcin,?asocha, Wies?aw,Pamin, Katarzyna,Po?towicz, Jan
-
p. 998 - 1010
(2016/04/20)
-
- PREPARATION METHOD OF CARBOXYLIC ACIDS OR KETONES USING OZONE, SINGLET STATE-OXYGEN ATOM OR HYDROXYL FREE RADICAL
-
A preparation method of carboxylic acids or ketones using ozone, singlet state oxygen atom O(1D) or hydroxyl free radical is provided. The method includes: filling ozone, singlet state oxygen atom O(1D) and/or hydroxyl free radical to cycloalkanes or benzenes at a pre-determined temperature and a pre-determined pressure in the presence or absence of light irradiation to produce carboxylic acids or ketones. The reaction occurs at room temperature and atmospheric pressure without producing harmful side products. The preparation method is a simple, low energy consuming, and eco-friendly method.
- -
-
Paragraph 0034; 0039
(2016/05/10)
-
- ENHANCED DIACID PRODUCTION WITH GENETICALLY MODIFIED MICRO-ORGANISMS
-
The present invention relates to a field of diacids, and more precisely to a method of producing diacids. The invention further relates to recombinant microorganisms comprising omega-oxidation and increased diacid production, and uses and methods related thereto.
- -
-
Page/Page column 28
(2016/12/12)
-
- An Easy Route to Enantiomerically Enriched 7- and 8-Hydroxy-stearic Acids by Olefin-Metathesis-Based Approach
-
The synthesis of enantiomerically enriched 7- and 8-hydroxy-stearic acids (7- and 8-HSA) has been successfully accomplished starting from chiral nonracemic 1-pentadecen-4-ol and 1-tetradecen-4-ol, respectively. Their Yamaguchi's esterification with 4-pentenoic and 5-hexenoic acids, respectively, afforded the suitable dienic esters which were submitted to ring-closing metathesis reaction. After hydrogenation and basic hydrolysis of the complex reaction mixture, chiral nonracemic 7- and 8-HSA were obtained in about 40% total yield.
- Boga, Carla,Drioli, Sara,Forzato, Cristina,Micheletti, Gabriele,Nitti, Patrizia,Prati, Fabio
-
supporting information
p. 1354 - 1358
(2016/05/24)
-
- Iron Catalysis for Room-Temperature Aerobic Oxidation of Alcohols to Carboxylic Acids
-
Oxidation from alcohols to carboxylic acids, a class of essential chemicals in daily life, academic laboratories, and industry, is a fundamental reaction, usually using at least a stoichiometric amount of an expensive and toxic oxidant. Here, an efficient and practical sustainable oxidation technology of alcohols to carboxylic acids using pure O2 or even O2 in air as the oxidant has been developed: utilizing a catalytic amount each of Fe(NO3)3·9H2O/TEMPO/MCl, a series of carboxylic acids were obtained from alcohols (also aldehydes) in high yields at room temperature. A 55 g-scale reaction was demonstrated using air. As a synthetic application, the first total synthesis of a naturally occurring allene, i.e., phlomic acid, was accomplished.
- Jiang, Xingguo,Zhang, Jiasheng,Ma, Shengming
-
supporting information
p. 8344 - 8347
(2016/07/26)
-
- Complexation of tetrakis(acetato)chloridodiruthenium with naphthyridine-2,7-dicarboxylate - Characterization and catalytic activity
-
The reaction of calcium naphthyridine-2,7-dicarboxylate (Cadcnp) with Ru2(OAc)4Cl in water resulted in the formation of Ca[Ru2(dcnp)(OAc)3]2 (3). X-ray crystal structural analysis of 3 confirmed its molecular structure and showed that the calcium ion binds to the lateral carboxylate groups of four neighboring anionic units of [Ru2(dcnp)(μ-OAc)3] and two acetone molecules to form a two-dimensional framework. The RuII-RuII valence state of the diruthenium core was supported by superconducting quantum interference device (SQUID) magnetometry [μeff (300 K) = 2.77 μB]. Complex 3 appears to be an efficient catalyst for the oxidative cleavage of olefins in aqueous media under mild conditions. Typically, the reaction of pulegone with NaIO4 in water catalyzed by 3 (1 mol-%) at 45 C afforded 3-methyladipic acid quantitatively. The reaction of calcium naphthyridine-2,7-dicarboxylate (Cadcnp) with Ru2(OAc)4Cl provides Ca[Ru2(dcnp)(OAc)3]2 as the exclusive product. The complex is catalytically active for the oxidative cleavage of olefins in aqueous media.
- Lee, Chia-Han,Wu, Cai-Ling,Hua, Shao-An,Liu, Yi-Hung,Peng, Shie-Ming,Liu, Shiuh-Tzung
-
p. 1417 - 1423
(2015/03/18)
-
- Oxidation of cyclooctene to suberic acid using perrhenate-containing composite ionic liquids as green catalysts
-
A series of quaternary ammonium perrhenate/3-hexyl-1-methyl-imidazolium hydrogen sulfate ([Hmim]HSO4) composite ionic liquids has been prepared. For the first time, the composite ionic liquids are used both as catalyst and solvent in oxidation of cyclooctene to suberic acid in the presence of hydrogen peroxide as a green oxidant. It was found that organic perrhenate salts play the important role in improving the selectivity of cyclooctene oxidation to suberic acid. The yield of suberic acid under the mild conditions is from good to high.
- Wang,Zhou,Yuan,Fu,Zang
-
p. 2378 - 2385
(2015/11/24)
-
- Role of added chloride ions in alteration of reaction pathway in the oxidation of cyclic ketones by dichloroisocyanuric acid - A kinetic study
-
Effect of added chloride ions on kinetics and pathway of reaction between cyclic ketones (five to eight membered rings) and dichloroisocyanuric acid (DCICA) was studied in aqueous acetic acid - perchloric acid medium. Formation of aliphatic dicarboxylic acids as the end products demonstrates the ring cleavage oxidation. Positive effect of acid and negative effect of dielectric constant on the reaction rate reveals a interaction between positive ion (oxidant in the form of H2OCl+) and dipolar substrate molecule. Zero and first orders by oxidant in absence and presence of added chloride ions illustrates the participation of substrate as enolic form of ketone and protonated ketone, respectively, in the rate determining steps. The observed order of reactivity of cyclic ketones (cyclohexanone > cyclooctanone > cyclopentanone > cycloheptanone) was explained on the bases of ring strain, change of hybridization and conformational considerations. The envisaged plausible mechanism based on order of reactants in presence and absence of added chloride ions was substantiated by the order of Arrhenius parameters.
- Lakshman Kumar,Venkata Nadh,Radhakrishnamurti
-
p. 376 - 383
(2015/02/19)
-
- On the importance of the relative stereochemistry of substituents in the formation of nine-membered lactones by ring-closing metathesis
-
The effects of isopropyl substituents and molar concentration of diastereomeric esters toward the formation of nine-membered unsaturated lactones, in the context of the synthesis of the intermediates of the antihypertensive drug aliskiren, have been studied
- Cusson, Jean-Philippe,Chénard, Etienne,Hanessian, Stephen
-
p. 1317 - 1324
(2015/08/05)
-
- ACYCLIC ALKENES VIA OZONOLYSIS OF MULTI-UNSATURATED CYCLOALKENES
-
A method of making a compound of formula (IIa) by selective ozonolysis of a compound of formula (I) is provided, wherein A is a C6-C10 alkene chain with at least one double bond, R1 is a C1-C10 alkyl, and R3 is an oxygen-containing functional group.
- -
-
Paragraph 00157
(2015/02/02)
-
- One-pot room-temperature conversion of cyclohexane to adipic acid by ozone and UV light
-
Nitric acid oxidation of cyclohexane accounts for ~95% of the worldwide adipic acid production and is also responsible for ~5 to 8% of the annual worldwide anthropogenic emission of the ozone-depleting greenhouse gas nitrous oxide (N2O). Here we report a N2O-free process for adipic acid synthesis.Treatment of neat cyclohexane, cyclohexanol, or cyclohexanone with ozone at room temperature and 1 atmosphere of pressure affords adipic acid as a solid precipitate. Addition of acidic water or exposure to ultraviolet (UV) light irradiation (or a combination of both) dramatically enhances the oxidative conversion of cyclohexane to adipic acid.
- Hwang, Kuo Chu,Sagadevan, Arunachalam
-
p. 1495 - 1498
(2015/02/19)
-
- METHOD OF MANUFACTURE OF OCTANEDIOIC ACID, PRECURSORS, AND DERIVATIVES
-
A method for the manufacture of 1,8-octanedioic acid comprises: reacting gamma-valerolactone with an alcohol in the presence of an acid or a base catalyst to provide an alkyl pentenoate, converting the alkyl pentenoate in the presence of a metathesis initiator to provide the dialkyl octenedioate, reacting the dialkyl octenedioate with hydrogen in the presence of a hydrogenation catalyst to provide a dialkyl 1,8-octanedioate and hydrolyzing the dialkyl 1,8-octanedioate to provide the 1,8-octanedioic acid.
- -
-
Paragraph 0091; 0092; 0093
(2014/10/04)
-
- Transformations of peroxide products of olefin ozonolysis in tetrahydrofuran in reactions with hydroxylamine and semicarbazide hydrochlorides
-
Treatment with hydroxylamine and semicarbazide hydrochlorides of peroxide products obtained by ozonolysis of olefins in tetrahydrofuran gives mainly carboxylic acids and their derivatives.
- Ishmuratov,Legostaeva,Garifullina,Botsman,Muslukhov,Ishmuratova,Tolstikov
-
p. 928 - 933
(2014/10/15)
-
- METHODS OF MAKING FUNCTIONALIZED INTERNAL OLEFINS AND USES THEREOF
-
A method of isomerizing a substance includes combining a substance including a terminal alkenyl group and a substance including a fluorosulfonic acid group in a reaction mixture, and forming a substance including a 2-alkenyl group from the substance including a terminal alkenyl group in the reaction mixture. The method may be used to functionalize a substance, as the substance including a 2-alkenyl group can be reacted with a functionalizing agent to form a substance including a first functional group. The methods may be used to form a dicarboxylic acid, such as suberic acid, from a renewable feedstock.
- -
-
Paragraph 00149-00150
(2014/06/23)
-
- Insights into gold-catalyzed synthesis of azelaic acid
-
A novel green route for the synthesis of azelaic and pelargonic acid via aerobic gold-catalyzed cleavage of 9,10-dihydroxystearic acid (DSA) was investigated recently. In this study, the examination of the reaction mechanism is described. The results of the application of 18O-labeled molecular oxygen and sodium hydroxide as well as of diastereomeric pure erythro- and threo-DSA were discussed. Assumed reaction intermediates were synthesized and subjected to the same reaction conditions as with DSA. As a conclusion from the obtained data, an oxidative dehydrogenation mechanism was postulated. Additionally, the aging of the gold catalyst used under different storage conditions was explored. the Partner Organisations 2014.
- Kulik, Anna,Martin, Andreas,Pohl, Marga-Martina,Fischer, Christine,Koeckritz, Angela
-
p. 1799 - 1806
(2014/04/17)
-
- COMPOUNDS AND THEIR METHODS OF USE
-
Compounds and compositions comprising compounds that inhibit glutaminase are described herein. Also described herein are methods of using the compounds that inhibit glutaminase in the treatment of cancer.
- -
-
Paragraph 0280
(2014/05/25)
-
- The effect of encapsulated Zn-POM on the catalytic activity of MIL-101 in the oxidation of alkenes with hydrogen peroxide
-
Zinc monosubstituted Keggin heteropolyanion [PZnMo2W 9O39]5- was electrostatically bound to nanocages of MIL-101 polymer matrix. The Zn-POM@MIL-101 catalyst was characterized by XRD, N2 adsorption, atomic absorption (AAS), and FT-IR spectroscopic methods. The catalytic activity of the new composite material, Zn-POM@MIL-101, was assessed in the oxidation of alkenes using aqueous hydrogen peroxide as oxidant. Zn-POM@MIL-101/H2O2 catalytic system demonstrated good catalytic activity in the oxidation reactions. Zn-POM@MIL-101 was reusable for three catalytic cycles. While the MIL-101 matrix is an active catalyst in these oxidation reactions, the presence of Zn-POM significantly changed the selectivity and reaction times. Copyright
- Saedi, Zahra,Tangestaninejad, Shaharm,Moghadam, Majid,Mirkhani, Valiollah,Mohammadpoor-Baltork, Iraj
-
experimental part
p. 463 - 473
(2012/05/20)
-
- METHOD FOR THE OXIDATION OF UNSATURATED ORGANIC COMPOUNDS
-
The present invention concerns a method for the oxidative cleavage of unsaturated carbon-carbon bonds into carboxylic acids or ketones using a manganese catalyst and hydrogen peroxide.
- -
-
Page/Page column 22-23
(2012/02/05)
-
- A one-pot method for the oxidation of unsaturated organic compounds
-
The present invention concerns a method for the oxidative cleavage of unsaturated carbon-carbon bonds into carboxylic acids or ketones using a manganese catalyst and hydrogen peroxide.
- -
-
Page/Page column 5
(2012/02/05)
-
- MIL-101 metal-organic framework: A highly efficient heterogeneous catalyst for oxidative cleavage of alkenes with H2O2
-
In the present work, a new and efficient method for direct oxidation of alkenes to carboxylic acids with H2O2 catalyzed by metal-organic framework MIL-101 is reported. In this transformation, the MIL-101 catalyzes the oxidation reactions by framework nodes and acts as a heterogeneous and reusable catalyst. The structure of MIL-101 was stable after three catalytic cycles.
- Saedi, Zahra,Tangestaninejad, Shahram,Moghadam, Majid,Mirkhani, Valiollah,Mohammadpoor-Baltork, Iraj
-
experimental part
p. 18 - 22
(2012/03/26)
-
- Tetrapropylammonium perruthenate catalyzed glycol cleavage to carboxylic (Di)acids
-
A new method to accomplish glycol cleavage to carboxylic (di)acids in one step using catalytic amounts of tetrapropylammonium perruthenate (TPAP) together with N-methylmorpholine N-Oxide (NMO) as the stoichiometric oxidant is presented. In addition to regenerating the active catalyst, the N-oxide stabilizes intermediary carbonyl hydrates and thereby shifts a crucial equilibrium. The mild oxidation protocol is applicable to a broad range of substrates providing the respective acids, diacids, or keto acids in high yields.
- Schmidt, Andrea-Katharina C.,Stark, Christian B. W.
-
supporting information; experimental part
p. 5788 - 5791
(2011/12/05)
-
- Excellent synthesis of adipic acid
-
A simple, straightforward, and environmentally benign protocol for the synthesis of adipic acid from oxidation of cyclohexanone with Oxone in the presence of 0.5mol% RuCl3·nH2O is reported. The reaction completes within a very short time even at room temperature. The generality of the method is shown successfully for synthesis of other C-5 to C-8 dicarboxylic acids.
- Rokhum, Lalthazuala,Bez, Ghanashyam
-
experimental part
p. 548 - 552
(2011/04/22)
-
- An efficient FeCl3-promoted O-alkyl cleavage of esters to carboxylic acids
-
A reliable and practical procedure for FeCl3-promoted ester cleavage has been developed. Lewis acids including TiCl4, ZnO and FeCl3 etc. were investigated as promoters for O-alkyl cleavage of carboxylic acid ester. Under optimal reaction conditions, FeCl3 (1.5 equiv.) was found to possess the highest activity and efficiently enhanced dealkylation of aryl esters, alkyl esters and aromatic heterocyclic esters to give their corresponding carboxylic acids in 54-98% yield, the method provides a complementary access to dealkylation of ester under neutral condition.
- Lian, Xiaoyan,Fu, Shaomin,Ma, Tongmei,Li, Shunbin,Zeng, Wei
-
experimental part
p. 443 - 447
(2012/02/03)
-
- Chemical and photochemical oxidation of organic substrates by ruthenium aqua complexes with water as an oxygen source
-
Two ruthenium aqua complexes were shown to be effective catalysts in chemical and photochemical oxidation of hydrocarbons. A remarkable activity (up to 90% yield and 100% selectivity) was performed in conversion of sulfide to sulfoxide by homogeneous photooxidation.
- Li, Fei,Yu, Miao,Jiang, Yi,Huang, Fang,Li, Yanqing,Zhang, Biaobiao,Sun, Licheng
-
supporting information; experimental part
p. 8949 - 8951
(2011/10/02)
-
- Catalytic oxidative cleavage of olefins by RuO4 organic solvent-free under ultrasonic irradiation
-
All the works reported about oxidative cleavage of olefins by the RuCl3/NaIO4 catalytic system have been performed in biphasic water/organic solvent(s). The first organic solvent-free oxidation of C{double bond, long}C double bond by 2% RuCl3/4.1 equiv NaIO4/H2O is described here using both the emulsifier Aliquat 336 and 20 kHz ultrasonic irradiation.
- Rup, Sandrine,Sindt, Michèle,Oget, Nicolas
-
scheme or table
p. 3123 - 3126
(2010/08/07)
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- Structure and properties of tungsten peroxopolyoxo complexes - Promising catalysts for organics oxidation. I. Structure of peroxocomplexes studied during the stepwise synthesis of tetra(diperoxotungsten)phosphate-tetra-n-butyl ammonium
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Catalysis via metal complexes has been studied using EXAFS and Raman spectroscopy. Main polyoxo- and peroxopolyoxocomplexes of tungsten, resulting from the interaction of phosphorus tungsten heteropolyacid with hydrogen peroxide in water solutions, were investigated with regard to their form and structure. Interaction was shown to reduce the nuclearity of forming complexes with respect to their precursor - H3PW12O40. The symmetry of oxygen environment of tungsten was found to change, distances W-W remaining the same. After complex [Bun4N] 3{PO4[WO(O2)2]4} is isolated, binuclear anion [W2O3(O2) 4(H2O)2]2- stays in the solution. Raman scattering, EXAFS and IR spectroscopy show that isolated peroxocomplex in its crystal state has four nuclei, and most probably retains this structure being dissolved in acetonitrile. Synthesized catalytic complex [Bu n4N]3{PO4[WO(O2) 2]4} was tested in oxidation of cyclic alkenes and alcohols with hydrogen peroxide. Complex [Bun4N] 3{PO4[WO(O2)2]4} was proved to provide higher yields of mono- and dicarbonic acids in comparison to in situ synthesized catalyst.
- Pai, Zinaida P.,Kochubey, Dimitry I.,Berdnikova, Polina V.,Kanazhevskiy, Vladislav V.,Prikhod'Ko, Irina Yu.,Chesalov, Yuriy A.
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experimental part
p. 122 - 127
(2010/12/25)
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- METHOD FOR PRODUCING CARBOXYLIC ACIDS BY OXIDATIVE CLEAVAGE OF UNSATURATED COMPOUNDS
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The invention provides a method of oxidative cleavage of an unsaturated carbon-carbon bond, said method comprising contacting a reactant molecule containing a carbon-carbon unsaturated bond with a catalytic system comprising (i) either a mixture of tungstate salt and tungstic acid or a mixture of a molybdate salt and molybdic acid; (ii) an aqueous solution of dihydrogen peroxide; (iii) a phase-transfer catalyst; and (iv) a carboxylic acid.
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Page/Page column 15-16
(2009/10/22)
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- Indium(III) chloride-catalyzed oxidative cleavage of carbon-carbon multiple bonds by tert-butyl hydroperoxide in water-a safer alternative to ozonolysis
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An efficient and general method for the oxidative cleavage of alkenes and alkynes using tert-butyl hydroperoxide and indium(III) chloride as catalyst in water to give the corresponding carboxylic acids or ketones has been achieved. The reaction conditions are compatible with sensitive moieties such as peptide bonds, tert-butyl carboxylic esters and N-Boc-protected tryptophan. The catalyst could be recycled.
- Ranu, Brindaban C.,Bhadra, Sukalyan,Adak, Laksmikanta
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p. 2588 - 2591
(2008/09/21)
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- Catalytic strategies for sustainable oxidations
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Several catalytic protocols for the oxidation of hydro-soluble substrates are presented that employ totally inorganic and robust polyoxometalate-based catalysts as well as porphyrin sensi-tizers, fullerenes and hybrid conjugates. Strategies for the imple-mentation of the system stability and efficiency are discussed.
- Carraro, Mauro,Sartorel, Andrea,Scorrano, Gianfranco,Carofiglio, Tommaso,Bonchio, Marcella
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experimental part
p. 1971 - 1978
(2009/04/07)
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- Cobalt-Catalyzed Oxidations in Volumetrically Expanded Liquids by Compressed Gases
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Oxidations of hydrocarbons, cycloalkanes and alkenes, arylalkanes, and a variety of other organic substrates are accomplished by cobalt-N-hydroxysuccinimide co-catalyzed reactions with dioxygen under unusually mild, near ambient conditions of temperature and pressure. The improved safety of the oxidation method and the high yields of product obtained make use of a unique combination of cobalt (II) complexes with N-hydroxysuccinimide. These autoxidation reactions do not have prolonged initiation times. Many of these reactions can be safely performed under normal chemical laboratory conditions and do not require specialized equipment or reagents.
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Page/Page column 8
(2008/12/06)
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- Ruthenium-catalyzed selective and efficient oxygenation of hydrocarbons with water as an oxygen source
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(Chemical Equation Presented) Water is not only the solvent but also the sole oxygen source in the smooth and efficient oxidation of organic compounds catalyzed by a RuII-pyridylamine-aqua complex with CeIV as the oxidant. An intermediate-spin RuIV-oxo complex is formed as the reactive species (see scheme; Sub = substrate). This catalytic system is durable and able to gain high turnover numbers for various substrates.
- Hirai, Yuichirou,Kojima, Takahiko,Mizutani, Yasuhisa,Shiota, Yoshihito,Yoshizawa, Kazunari,Fukuzumi, Shunichi
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experimental part
p. 5772 - 5776
(2009/03/11)
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- Improved procedure for ruthenium-catalyzed oxidative cleavage of alkenes with IG(OH)5
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Oxidative cleavage of alkenes to carboxylic acids catalyzed by cis-[RuCl2-(bipy)2]·2H2O in the presence of IO(OH)5 has been studied in a biphasic (CH3CN-CCl 4-H2O; 1:1:2 v/v) solvent system. Ruthenium tetraoxide seems to be the active catalyst species. Copyright Taylor & Francis LLC.
- Shoair, Abdel Ghany F.,Mohamed, Ramadan H.
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- Exploring the synthetic applicability of a cyanobacterium nitrilase as catalyst for nitrile hydrolysis
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The substrate specificity and synthetic applicability of the nitrilase from cyanobacterium Synechocystis sp. strain PCC 6803 have been examined. This nitrilase catalyzed the hydrolysis of both aromatic and aliphatic nitriles to the corresponding acids in high yields. Furthermore, the stereoselective hydrolysis of phenyl-substituted β-hydroxy nitriles to (S)-enriched β-hydroxy carboxylic acids and selective hydrolysis of α,ω- dinitriles with five or less methylene groups to ω-cyano carboxylic acids have been achieved. This suggested that nitrilase from Synechocystis sp. PCC 6803 could be a useful enzyme catalyst for the "green" nitrile hydrolysis. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Mukherjee, Chandrani,Zhu, Dunming,Biehl, Edward R.,Hua, Ling
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p. 5238 - 5242
(2007/10/03)
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- PROCESS FOR PRODUCING ALIPHATIC DICARBOXYLIC ACID COMPOUND
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The present invention discloses a process for producing an aliphatic dicarboxylic acid compound, which comprises oxidizing, with a nitrite or a nitrate in the presence of trifluoroacetic acid, an alicyclic secondary alcohol compound or an alicyclic ketone compound, in each of which at least one methylene group is bonded to the carbon atom having hydroxyl group bonded thereto or the carbon atom as a member of carbonyl group, wherein the reaction is conducted in the presence of water of 5 mass % or less relative to 100 mass % of the total of the trifluoroacetic acid and the water.
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Page/Page column 6-7
(2008/06/13)
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- Synthesis and evaluation of coumermycin A1 analogues that inhibit the Hsp90 protein folding machinery
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(Chemical Equation Presented) The coumarin antibiotics are not only potent inhibitors of DNA gyrase but also represent the most effective C-terminal inhibitors of 90 kDa heat shock proteins (Hsp90) reported thus far. In contrast to the N-terminal ATP-binding site, little is known about the Hsp90 C-terminus. In addition, very limited structure-activity relationships exist between this class of natural products and Hsp90. In this letter, the syntheses of dimeric coumarin analogues are presented along with their inhibitory values in breast cancer cell lines.
- Burlison, Joseph A.,Blagg, Brian S. J.
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p. 4855 - 4858
(2007/10/03)
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- Ruthenium catalysed oxidation without CCl4 of oleic acid, other monoenic fatty acids and alkenes
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Ruthenium catalysed oxidation of alkenes and monoenic fatty acids is reported. The study of the influence of cosolvents (H2O/MeCN/X) shows that toxic CCl4 initially used in the Sharpless system (H 2O/MeCN/CCl4) can be avoided and demonstrates that the oxidative cleavage of CC bond could be accomplished in good yields with H 2O/MeCN/AcOEt solvent system in a ratio 3/2/2, respectively.
- Zimmermann, Fran?ois,Meux, Eric,Mieloszynski, Jean-Luc,Lecuire, Jean-Marie,Oget, Nicolas
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p. 3201 - 3203
(2007/10/03)
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- Catalytic oxidation of olefins and alcohols with hydrogen peroxide in a two-phase system giving mono- and dicarboxylic acids
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The present study considered the influence of various factors on the catalytic activity of systems based on a combination of tetrakis(oxodiperoxotungsto)phosphate(3-) with quaternary ammonium cations, for example, with methyltri-n-octylammonium [Me(n-C8H17) 3N]+. The catalysts were tested in oxidation of cycloolefins (cyclohexene and cyclooctene), alcohols (octan-1-ol and phenylmethanol), and unsaturated fatty acids (cis-9-octadecenoic and 12-hydroxy-9Z-octadecenoic acids) with a 30% hydrogen peroxide solution. These reactions proceed under mild conditions (atmospheric pressure, 80-90°C) to give carboxylic acids. The catalytic systems were characterized by vibrational (IR and Raman) spectroscopy. The state of the systems formed from various precursors, viz., polyoxometallates and phase-transfer catalysts, was studied. It was demonstrated for the first time that the structure formation of peroxo complexes depends on the nature of the halide anion of the quaternary ammonium salt used. The melting points of individual catalytic complexes were determined. The optimal conditions for oxidation were found.
- Pai,Tolstikov,Berdnikova,Kustova,Khlebnikova,Selivanova,Shangina,Kostrovskii
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p. 1847 - 1854
(2007/10/03)
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