- Production of dicarboxylic acids from novel unsaturated fatty acids by laccase-catalyzed oxidative cleavage
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The establishment of renewable biofuel and chemical production is desirable because of global warming and the exhaustion of petroleum reserves. Sebacic acid (decanedioic acid), the material of 6,10-nylon, is produced from ricinoleic acid, a carbonneutral material, but the process is not eco-friendly because of its energy requirements. Laccase-catalyzing oxidative cleavage of fatty acid was applied to the production of dicarboxylic acids using hydroxy and oxo fatty acids involved in the saturation metabolism of unsaturated fatty acids in Lactobacillus plantarum as substrates. Hydroxy or oxo fatty acids with a functional group near the carbon-carbon double bond were cleaved at the carbon-carbon double bond, hydroxy group, or carbonyl group by laccase and transformed into dicarboxylic acids. After 8 h, 0.58 mM of sebacic acid was produced from 1.6 mM of 10-oxo-cis-12,cis-15-octadecadienoic acid (αKetoA) with a conversion rate of 35% (mol/mol). This laccase-catalyzed enzymatic process is a promising method to produce dicarboxylic acids from biomass-derived fatty acids.
- Takeuchi, Michiki,Kishino, Shigenobu,Park, Si-Bum,Kitamura, Nahoko,Watanabe, Hiroko,Saika, Azusa,Hibi, Makoto,Yokozeki, Kenzo,Ogawa, Jun
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Read Online
- A direct synthesis of carboxylic acidsviaplatinum-catalysed hydroxycarbonylation of olefins
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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
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Read Online
- Six New Polyacetylenic Alcohols from the Marine Sponges Petrosia sp. and Halichondria sp.
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Six new polyacetylenic alcohols, termed strongylotriols A and B; pellynols J, K, and L; and isopellynol A, together with three known polyacetylenic alcohols, pellynols A, B, and C were isolated from the marine sponges Petrosia sp., and Halichondria sp. collected in Okinawa, Japan. Their planer structures were determined based on 2D-NMR and mass spectrometric analysis of the degraded products by RuCl3 oxidation. The absolute stereochemistry of isolates was examined by their Mosher's esters. The strongylotriols were found to be optically pure compounds, whereas the pellynols are diastereomeric mixtures at the C-6 position. Proliferation experiments using the HeLa and K562 cell lines suggested that the essential structural units for activity are the "hexa-2,4-diyn-1,6-diol" and "pent-1-en-4-yn-3-ol" on the termini.
- Gabriel, Adeyemi Francis,Li, Zhen,Kusuda, Ryouhei,Tanaka, Chiaki,Miyamoto, Tomofumi
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Read Online
- Aerobic oxidation of cycloalkanes, alcohols and ethylbenzene catalyzed by the novel carbon radical chain promoter NHS (N-hydroxysaccharin)
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Replacement of Ishii's N-hydroxyphthalimide (NHPI) with the novel carbon radical chain promoter N-hydroxysaccharin (NHS) affords, in combination with metal salts, notably Co, or other additives, selective catalytic autoxidation of hydrocarbons, alcohols and alkylbenzenes under mild conditions (25-100°C, O2 1 atm). The effects of solvent, temperature and the nature of the additives were investigated to give an optimised oxidation protocol for the various systems. The NHS/Co combination was more reactive than NHPI/Co in the autoxidation of cycloalkanes. In contrast, the opposite order of reactivity was observed in the autoxidation of ethylbenzene and alcohols. It is suggested, on the basis of bond dissociation energy (BDE) considerations, that this is a result of a change in the rate-limiting step with the more reactive ethylbenzene and alcohol substrates. In the autoxidation of the model cycloalkane, cyclododecane, the best results (90% selectivity to a 4:1 mixture of alcohol and ketone at 24% conversion) were obtained with NHS/Co(acac)3 in PhCF3 at 80°C. Competition experiments revealed that, in contrast to what is commonly believed, formation of the dicarboxylic acid by ring opening is not a result of further oxidation of the ketone product. It is suggested that ring opened products are a result of β-scission of the cycloalkoxy radical formed via (metal-catalysed) decomposition of the hydroperoxide. This is suppressed in the presence of NHS (or NHPI) which efficiently scavenge the alkoxy radicals.
- Baucherel, Xavier,Gonsalvi, Luca,Arends, Isabel W. C. E.,Ellwood, Simon,Sheldon, Roger A.
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Read Online
- Molecularization of Bitter Off-Taste Compounds in Pea-Protein Isolates (Pisum sativum L.)
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Activity-guided fractionations, combined with taste dilution analyses (TDA), were performed to locate the key compounds contributing to the bitter off-taste of pea-protein isolates (Pisum sativum L.). Purification of the compounds perceived with the highe
- Gl?ser, Peter,Dawid, Corinna,Meister, Stefanie,Bader-Mittermaier, Stephanie,Schott, Michael,Eisner, Peter,Hofmann, Thomas
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Read Online
- A Very Useful and Mild Method for the Protection and Deprotection of Carboxylic Acids
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3-Methylbut-2-enoate carboxylic acid can be a good protecting group of carboxylic acids and can be removed easily by using iodine in cyclohexane at room temperature.Key words: Protection, deprotection, 3-methylbut-2-enoate carboxylic acid, iodine.
- Cossy, Janine,Albouy, Arnaud,Scheloske, Michael,Pardo, Domingo Gomez
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Read Online
- Synthesis of Dicarboxylic Acids from Aqueous Solutions of Diols with Hydrogen Evolution Catalyzed by an Iridium Complex
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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
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- Direct and Selective Synthesis of Adipic and Other Dicarboxylic Acids by Palladium-Catalyzed Carbonylation of Allylic Alcohols
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A general and direct synthesis of dicarboxylic acids including industrially important adipic acid by palladium-catalyzed dicarbonylation of allylic alcohol is reported. Specifically, the combination of PdCl2 and a bisphosphine ligand (HeMaRaphos) promotes two different carbonylation reactions with high activity and excellent selectivity.
- Beller, Matthias,Ge, Yao,Huang, Weiheng,Jackstell, Ralf,Liu, Jiawang,Neumann, Helfried,Yang, Ji
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supporting information
p. 20394 - 20398
(2020/09/21)
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- PROCESS FOR THE CO-PRODUCTION OF LONG CHAIN AMINO ACIDS AND DIBASIC ACIDS
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There is disclosed a process for the co-production of long chain ω-amino acid and long chain dibasic acid, comprising: (1) reacting long chain ketoacid derivative with hydroxylamine or subjecting ketoacid derivative to an ammoximation to yield oxime derivative; (2) subjecting oxime derivative to Beckmann rearrangement to yield a mixture of mixed amide derivatives; (3) hydrolyzing the mixed amide derivatives to produce long chain ω-amino acid and long chain dibasic acid.
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Paragraph 0063-0065
(2019/02/01)
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- Synthesis of medium-chain carboxylic acids or α,ω-dicarboxylic acids from cellulose-derived platform chemicals
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Medium-chain fatty acids and their derivatives have important applications in the energy and chemical industries. Thus, we have prepared a series of medium-chain fatty acids by the selective hydrodeoxygenation of the aldol condensation products derived from cellulose using a metal triflate and Pd/C catalyst system. The selective retention of the carboxyl group is a notable feature of this catalytic system.
- Li, Xing-Long,Zhang, Kun,Jiang, Ju-Long,Zhu, Rui,Wu, Wei-Peng,Deng, Jin,Fu, Yao
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supporting information
p. 362 - 368
(2018/02/07)
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- Process for producing long chain amino acids and dibasic acids
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There is disclosed a process for the production of long chain amino acid and long chain dibasic acid, comprising: (1) reacting long chain keto fatty acid with hydroxylamine or subjecting keto fatty acid to an ammoximation reaction to yield an oxime fatty acid; (2) subjecting the oxime fatty acid to the Beckmann rearrangement to yield a mixture of two amide fatty acids; (3) hydrolyzing the mixed amide fatty acids to produce long chain amino acid, long chain dibasic acid, short chain alkylamine, and alkanoic acid.
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- Microalgae lipids as a feedstock for the production of benzene
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A two-step one-pot synthesis of benzene from the five-fold unsaturated fatty acid eicosapentaenoic acid (EPA), a component of microalgae oils, is presented. By a sequence of olefin metathesis and the catalytic dehydrogenation of the resulting 1,4-cyclohexadiene, two equivalents of benzene are effectively formed per EPA substrate molecule. As the only major by-products, 5-octenoic acid and 5-decenedioic acid are formed. Performing the dehydrogenation step under hydrogen pressure results in the formation of their saturated analogues, sebacic acid and octanoic acid, both desirable products, while the simultaneous dehydrogenation step to benzene is not hampered.
- Pingen, Dennis,Zimmerer, Julia,Klinkenberg, Nele,Mecking, Stefan
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p. 1874 - 1878
(2018/04/30)
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- Preparation method of 1,10-sebacic acid
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The invention discloses a preparation method of 1,10-sebacic acid. The preparation method includes: subjecting substance A to hydrolyzing and ring opening in an acid environment to obtain 4,7-diketone-1, and 10-sebacic acid; subjecting 4,7-diketone-1, 10-sebacic acid, hydrogen, trifluoromethanesulfonic salt and a hydrogenation catalyst to hydrodeoxygenation to obtain the 1,10-sebacic acid. The preparation method is good in atom economy, high in product yield, high in product purity, less in environment pollution, simple in process route, convenient in operation, cheap in raw materials which are easy to obtain and suitable for industrialized mass production.
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Paragraph 0077; 0082; 0087; 0092; 0097; 0102; 0107
(2018/03/01)
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- Cp? versus Bis-carbonyl iridium precursors as CH oxidation precatalysts
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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.
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p. 199 - 206
(2017/11/27)
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- The aliphatic dicarboxylic acid compound (by machine translation)
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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.
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Paragraph 0040; 0049; 0050
(2017/08/02)
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- Configurational Assignment of ‘Cryptochiral’ 10-Hydroxystearic Acid Through an Asymmetric Catalytic Synthesis
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An asymmetric catalytic total synthesis of (S)-10-hydroxystearic acid (1) for comparison of its absolute configuration to that of samples obtained by fermentative hydration of oleic acid is reported. The synthesis involves two catalytic key-steps, namely Ru-catalyzed anti-Markovnikov hydration of 9-decynoic acid (7) to 10-oxodecanoic acid (5), followed by titanium-mediated asymmetric catalytic addition of dioctylzinc (25) to 5 in presence of the chiral ligand N,N’-((1R,2R)-cyclohexane-1,2-diyl)bis(1,1,1-trifluoromethanesulfonamide) (6). The synthesis is short and efficient and avoids use of protecting groups. Ozonolysis of 10-undecynoic acid (9) to 5 provides an alternative entry point into the synthetic route. The double dehydrobromination of (ω,ω-1)-dibromoalkanoic acids to ω-alkynoic acids under a variety of conditions was investigated with 10,11-dibromoundecanoic acid (11) as model substrate and using qNMR to quantify all reaction products. The synthetic approaches presented here have the potential to be generalized to the asymmetric catalytic synthesis of a variety of n-hydroxy-fatty acids.
- Brunner, Andreas,Hintermann, Lukas
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p. 928 - 943
(2016/12/09)
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- COMBINED SYNTHESIS OF A NITRILE-ESTER/ACID AND OF A DIESTER/DIACID
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A method for the combined synthesis of a mono-unsaturated nitrile-ester(acid) and of a bi-functional carbonyl compound, wherein it includes a step including the cross metathesis mc1 of an unsaturated fatty acid/ester compound with an unsaturated nitrile compound, in which mc1 is performed with partial conversion such as to obtain and recover, separately, at least the following products: a mono-unsaturated nitrile-ester/acid and a symmetrical compound, diester or diacid respectively including a double bond located in the middle of the molecular chain of compound, and subsequently a step including the oxidation cleavage cp2 of the double bond of compound, such as to form a single type of carbonyl compound having formula R2-(CH2)n-COR′, in which R′ is H or OH, depending on the operating conditions selected for the oxidation cleavage cp2. Also, the production of monomers for the polymer industry.
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Paragraph 0139-0140; 0145
(2016/03/13)
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- DMF-mediated deprotection of bulky silyl esters under neutral and fluoride-free conditions
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Bulky TBDPS and TIPS carboxylic esters were efficiently cleaved by a green and mild protocol using only DMF-H2O (20:1) at 70 °C. The neutral conditions tolerate various common acid- and base-labile functionalities, including alkyl and aryl silyl ethers.
- Chen, Bo,Sun, Hui-Xia,Qin, Jian-Feng,Wang, Bing
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p. 253 - 255
(2016/01/12)
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- PROCESS FOR MANUFACTURING A CLEAVED PRODUCT FROM A RICINIC COMPOUND
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The invention pertains to a method for manufacturing a cleaved product from a ricinic compound comprising reacting at a temperature of at least 150°C at least a ricinic compound and at least one alkali in the presence of at least one thinning agent selected from the group consisting of long chain phenol derivatives of formula (I) herein below; wherein: n and m, equal to or different from each other, are integers equal to 1, 2 or 3; p is zero or an integer of 1 to 3; RLong is a long-chain hydrocarbon group having 6 to 36 carbon atoms; RShort is a short-chain hydrocarbon group having 1 or 2 carbon atoms.
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Paragraph 0060
(2015/02/19)
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- EFFICIENT SEPARATION OF SEBACIC ACID FROM ALKALI PHENOLATE BY METHANOL EXTRACTION UPON REFLUX
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The invention pertains to a process for the recovery of alkali phenolate derivative from a solid mixture comprising the same, in admixture with alkaline salts of sebacic acid, said process comprising multiple methanol extraction steps, and to the use of such recovery technique in the manufacture of sebacic acid from castor oil/ricinoleic acid.
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Paragraph 0052
(2015/02/02)
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- Structurally Simple Benzyl-Type Photolabile Protecting Groups for Direct Release of Alcohols and Carboxylic Acids
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Structurally simple benzyl-type photolabile protecting groups (PPGs) have been developed to release alcohols and carboxylic acids. Release of two substrates from one PPG chromophore has also been accomplished. (Chemical Equation Presented).
- Wang, Pengfei,Lu, Wenya,Devalankar, Dattatray A.,Ding, Zhenying
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p. 2114 - 2117
(2015/05/13)
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- Palladium on carbon-catalyzed aqueous transformation of primary alcohols to carboxylic acids based on dehydrogenation under mildly reduced pressure
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The catalytic dehydrogenation of alcohols to carbonyl products is a green sustainable oxidation with no production of waste except for hydrogen, which can be an energy source. Additionally, a reusable heterogeneous catalyst is valuable from the viewpoint of process chemistry and water is a green solvent. We have accomplished the palladium on carbon (Pd/C)-catalyzed dehydrogenation of primary alcohols to carboxylic acids in water under a mildly reduced pressure (800 hPa). The reduced pressure can be easily controlled by the vacuum controller of the rotary evaporator to remove the excess of generated hydrogen, which causes the reduction (reverse reaction) of aldehydes to alcohols (starting materials) and other undesirable side reactions. The present method is applicable to the reaction of various aliphatic and benzylic alcohols to the corresponding carboxylic acids, and the Pd/C could be reused at least 5 times.
- Sawama, Yoshinari,Morita, Kosuke,Asai, Shota,Kozawa, Masami,Tadokoro, Shinsuke,Nakajima, Junichi,Monguchi, Yasunari,Sajiki, Hironao
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supporting information
p. 1205 - 1210
(2015/04/22)
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- Ozonolytic transformations of 10-undecenoic acid in various solvents through the action of hydroxylamine and semicarbazide hydrochlorides
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Ozonolytic transformations of 10-undecenoic acid, which is available from castor oil, were studied. Syntheses of several α,ω-bifunctional sebacic acid derivatives were developed.
- Ishmuratov,Legostaeva,Nasibullina,Garifullina,Botsman,Tolstikov
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p. 594 - 597
(2015/02/02)
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- Multistep enzymatic synthesis of long-chain α,ω-Dicarboxylic and ω-hydroxycarboxylic acids from renewable fatty acids and plant oils
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A multistep enzyme catalysis was successfully implemented to produce long-chain α,ω-dicarboxylic and ω-hydroxycarboxylic acids from renewable fatty acids and plant oils. Sebacic acid as well as ω-hydroxynonanoic acid and ω-hydroxytridec-11-enoic acid were produced from oleic and ricinoleic acid. Copyright
- Song, Ji-Won,Jeon, Eun-Yeong,Song, Da-Hyun,Jang, Hyun-Young,Bornscheuer, Uwe T.,Oh, Deok-Kun,Park, Jin-Byung
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supporting information
p. 2534 - 2537
(2013/04/23)
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- Divergent process for C10, C11 and C12 ω-amino acid and α,ω-dicarboxylic acid monomers of polyamides from castor oil as a renewable resource
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Polyamides have great potentials for diverse applications and the present production of their monomers mostly relies on resources from fossil fuel. Starting from undecylenic acid, a natural resource, we have developed both divergent and efficient processes for C10, C11 and C 12 ω-amino acid and α,ω-dicarboxylic acid monomers of the polyamides.
- Koh, Moo-Hyun,Kim, Hyeonjeong,Shin, Nara,Kim, Hyun Su,Yoo, Dongwon,Kim, Young Gyu
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experimental part
p. 1873 - 1878
(2012/08/07)
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- Selective oxoammonium salt oxidations of alcohols to aldehydes and aldehydes to carboxylic acids
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The oxidation of alcohols to aldehydes using stoichiometric 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (1) in CH2Cl2 at room temperature is a highly selective process favoring reaction at the carbinol center best able to accommodate a positive charge. The oxidation of aldehydes to carboxylic acids by 1 in wet acetonitrile is also selective; the rate of the process correlates with the concentration of aldehyde hydrate. A convenient and high yield method for oxidation of alcohols directly to carboxylic acids has been developed.
- Qiu, Joseph C.,Pradhan, Priya P.,Blanck, Nyle B.,Bobbitt, James M.,Bailey, William F.
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supporting information; experimental part
p. 350 - 353
(2012/03/09)
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- Oxidation of benzyl alcohols, benzyl halides, and alkylbenzenes with oxone
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Oxidation of benzyl alcohols, benzyl halides, and alkylbenzenes to their corresponding oxidation products has been shown to be accomplished directly with oxone. The methodology that involves mere stirring/heating of the reactants and oxone in acetonitrile/water (1:1, v/v) is simple and practical, but is limited to substrates that do not contain sensitive functionalities and heteroaromatic rings.
- Parida, Keshaba Nanda,Jhulki, Samik,Mandal, Susovan,Moorthy, Jarugu Narasimha
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p. 9763 - 9768,6
(2020/08/20)
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- Catalytic oxidative cleavage of olefins by RuO4 organic solvent-free under ultrasonic irradiation
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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
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scheme or table
p. 3123 - 3126
(2010/08/07)
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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
(2008/06/13)
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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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- Carboxylic acids from primary alcohols and aldehydes by a pyridinium chlorochromate catalyzed oxidation
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A facile and quantitative preparation of carboxylic acids by a pyridinium chlorochromate (PCC) catalyzed (2 mol%) oxidation of primary alcohols and aldehydes using 2.2 equivalents and 1.1 equivalents of H5IO 6, respectively, in acetonitrile is described here. Georg Thieme Verlag Stuttgart.
- Hunsen, Mo
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p. 2487 - 2490
(2007/10/03)
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- In situ generation of o-lodoxybenzoic acid (IBX) and the catalytic use of it in oxidation reactions in the presence of oxone as a co-oxidant
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(Chemical Equation Presented) Catalytic use of o-iodoxybenzoic acid (IBX) in the presence of Oxone as a co-oxidant is demonstrated for the oxidation of primary and secondary alcohols in user- and eco-friendly solvent mixtures. Also demonstrated is the in situ (re)oxidation of 2-iodosobenzoic acid (IBA) and even commercially available 2-iodobenzoic acid (2IBAcid) by Oxone to IBX allowing one to use these less hazardous reagents, in place of potentially explosive IBX, as catalytic oxidants.
- Thottumkara, Arun P.,Bowsher, Michael S.,Vinod, Thottumkara K.
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p. 2933 - 2936
(2007/10/03)
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- Fluorochromate-catalyzed periodic acid oxidation of alcohols and aldehydes
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Preparation of aldehydes and ketones from alcohols, and carboxylic acids from alcohols and aldehydes using pyridinium fluorochromate (PFC) as a catalyst and H5IO6 as the terminal oxidant is described here.
- Hunsen, Mo
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p. 1356 - 1360
(2007/10/03)
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- Method for preparing sebacic acid and octanol-2
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A process for producing a cleaved product from a ricinic compound by a high temperature reaction, achieved by combining an alkali in aqueous solution, a thinning agent, and a ricinic compound at a first temperature sufficient to distill off volatiles in the reaction mixture and then raising the temperature to a temperature sufficient to initiate a pyrolysis reaction and form a cleaved product from the ricinic compound, wherein the amount of thinning agent is in at a level sufficient to reduce the solidification of the mass during the reaction and foaming and increase the yield and purity of the products. The thinning agent is an isocarboxylic acid, an isoaldehyde or an isoalcohol containing from 5 to 13 carbon units. The thinning agent is relatively inexpensive, non-volatile and resistant to decomposition under the reaction conditions, easy to recover, and a non-foaming agent. The ricinic compound is castor oil, a ricinoleate, a ricinic acid ester, a ricinoleic acid, a ricinoleic acid amide, a ricinoleic acid ester, a sulfonated ricinoleate, a ricinic ester, a ricinic alcohol, ricinoleyl acid, a ricinoleyl acid amide, ricinoleyl alcohol, ricinoleyl alcohol. ester, an alkali ricinoleate or a mixture thereof The reaction mixture is acidified at the end of the reaction to allow for effective recovery of the thinning agent and the products. The invention also relates to the reaction mixture used in this cleavage reaction. The invention is useful in producing cleaved products of high yield and purity.
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Page column 7
(2008/06/13)
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- Ruthenium-catalysed cleavage of alkenes and alkynes to carboxylic acids
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Catalysis of alkene and alkyne cleavage to carboxylic acids by ruthenium trichloride in the presence of an excess of periodic acid has been studied in biphasic H2O - CCl4-CH3CN media, and is found to be simple and effective. The active catalyst is shown to be RuO4.
- Griffith, William P.,Shoair, Abdel G.,Suriaatmaja, Maria
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p. 3091 - 3095
(2007/10/03)
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- Method for preparing cleaved products from castor oil or derivatives thereof
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A process for producing a cleaved product from castor oil, or derivatives thereof, by high temperature caustic oxidation reaction accomplished by combining at least one chemically inert heat transfer fluid, a catalyst, and an alkali in aqueous solution to form a first mixture wherein the diluent is present in an amount sufficient to reduce foaming and solidification of the mixture while increasing the yield and improving the purity and adding a ricinic compound to the first mixture to form a second mixture. The temperature of the second mixture is raised to a level sufficient to conduct pyrolysis, and the cleaved product produced thereby is recovered by adding an acid to the reaction mixture in an amount sufficient to acidify the reaction mixture down below a pH of about 6. The invention further relates to the reaction mixture used to produce the cleaved products. The present invention provides higher product yields and purer cleaved products produced by the oxidation of castor oil or its derivatives than conventionally obtained.
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- Oxidation catalytic system and oxidation process using the same
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A substrate (e.g., a cycloalkane, a polycyclic hydrocarbon, an aromatic compound having a methyl group or methylene group adjacent to an aromatic ring) is oxidized with oxygen in the presence of an oxidation catalyst comprising an imide compound of the following formula (1) (e.g., N-hydroxyphthalimide), and a co-catalyst (except phosphovanadomolybdic acid) containing an element selected from the group consisting of Group 2A elements of the Periodic Table of Elements, transition metals (Group 3A to 7A elements, Group 8 elements, Group 1B elements and Group 2B elements of the Periodic Table of Elements) and Group 3B elements of the Periodic Table of Elements, for the formation of an oxide (e.g., a ketone, an alcohol, a carboxylic acid): STR1 wherein R1 and R2 represent a substituent such as a hydrogen atom or a halogen atom, or R1 and R2 may together form a double bond or an aromatic or nonaromatic 5- to 12-membered ring, X is O or OH, and n is 1 to 3.
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- Convenient synthesis of chiral cyclophanes that can coordinate to metals
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Optically pure cyclophanes possessing a 1,3-dicarbonyl moiety were conveniently synthesized from alkanedioyl dichloride in four steps. The intramolecular [4+2]cycloaddition of bis(acylketene)s generated by thermal decomposition of bis(4,6-dioxo-1,3-dioxane) proceeded smoothly, giving cyclophane pyranones in high yields. The compounds possessing 7-10 bridging methylenes were resolved by imine formation with (R)-1-phenylethylamine, followed by basic hydrolysis. These cyclophanes are optically active versions of acetylacetone or salicylaldehyde and formed complexes with metals such as copper and europium. X-ray analysis of the chiral copper complex indicated the pentacoordinated structure of the copper metal with syn configuration of the two bridging chains.
- Sato, Masayuki,Uehara, Fumiaki,Sato, Kayo,Yamaguchi, Masahiko,Kabuto, Chizuko
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p. 8270 - 8276
(2007/10/03)
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- Efficient oxidative cleavage of olefins to carboxylic acids with hydrogen peroxide catalyzed by methyltrioctylammonium tetrakis(oxodiperoxotungsto)phosphate(3-) under two-phase conditions. Synthetic aspects and investigation of the reaction course
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The oxidative cleavage of alkenes to carboxylic acids with 40% w/v aqueous hydrogen peroxide catalyzed by methyltrioctylammonium tetrakis(oxodiperoxotungsto)phosphate(3-) (1a) is reported to occur in high yields and selectivities under two-phase conditions in the absence of organic solvents. On the basis of a study of the reaction, two main reaction pathways leading to acids have been recognized, the first one involving the perhydrolysis and the second one the hydrolysis of the epoxide initially formed. The "perhydrolytic" reaction pathway appears to play a primary role in the oxidation of medium- and long-chain alkenes to acids, while it intervenes to a rather limited extent in the oxidation of arylalkenes and C5-C7 cycloalkenes. The occurrence of this pathway has been proved by the isolation of the intermediate β-hydroperoxy alcohols and their transformation into acids with H2O2 and la. The course of this transformation, involving an initial oxidation (to α-oxo hydroperoxide) or decomposition (to carbonyl compounds) of the β-hydroperoxy alcohol intermediate, is described. The primary oxidation products, α-hydroperoxy ketones, have been isolated in the case of internal β-hydroperoxy alcohols, whereas their presence has been evidenced with terminal β-hydroperoxy alcohols bearing a secondary hydroxy group. Hydrogen peroxide concentration appears to exert a remarkable influence on medium acidity, and its effects on the reaction efficiency are shown.
- Antonelli, Ermanno,D'Aloisio, Rino,Gambaro, Mario,Fiorani, Tiziana,Venturello, Carlo
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p. 7190 - 7206
(2007/10/03)
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- Direct conversion of cyclohexane into adipic acid with molecular oxygen catalyzed by N-hydroxyphthalimide combined with Mn(acac)2 and Co(OAc)2
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Direct conversion of cyclohexane into adipic acid was achieved by the use of the radical catalyst, N-hydroxyphthalimide (NHPI), in the presence of a small amount of a transition metal. For instance, cyclohexane could be converted into adipic acid in 73% selectivity at 73% conversion under atmospheric oxygen (1 atm) in the presence of NHPI (10 mol %) and Mn(acac)2 (1 mol %) at 100 °C for 20 h. ESR measurements show that the formation of phthalimide N-oxyl generated from NHPI with O2 was assisted by Co(II) species. Thus, the oxidation of cyclohexane to adipic acid was found to be enhanced by the addition of a small amount of Co(OAc)2 to the NHPI/Mn(acac)2 system. The NHPI-catalyzed oxidation of cyclohexane provides an attractive direct method which has long been desired in the chemical industry for the manufacturing of adipic acid. The present oxidation seems to be the first practical environmentally friendly process, in which nitric acid is not used as the oxidant, for the production of adipic acid from cyclohexane.
- Iwahama, Takahiro,Syojyo, Kouichi,Sakaguchi, Satoshi,Ishii, Yasutaka
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p. 255 - 260
(2013/09/08)
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- Metronidazole twin ester prodrugs: Synthesis, physicochemical properties, hydrolysis kinetics and antigiardial activity
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A series of identical twin esters 3a-e of metronidazole was synthesized and evaluated as potential prodrugs with improved physicochemical and pharmacokinetic properties. The synthesis of the twin esters 3a-e was achieved by interaction of metronidazole with the respective dicarboxylic acid anhydride or their dichloride. Their structures were verified by elemental and spectroscopic analyses. The lipophilicity of metronidazole and the prodrugs 3a-e, expressed as R(m), values, were determined using reversed- phase TLC and revealed enhanced lipophilic properties compared with metronidazole. Reversion kinetics of the parent drug from its twin esters was investigated in aqueous buffer solutions (pH 1.2 and 7.4) as well as in biological media (80% human plasma and 20% rat liver homogenate) at 37 °C using HPLC. In all cases, the hydrolysis followed pseudo-first-order kinetics in a two-step reaction (k1 and k2) via the intermediate formation of the respective metronidazole hemiester. All the synthesized twin ester prodrugs 3a-e were proved to be chemically stable at acidic pH (t(1/2) ~ 25-72 h) and also at the physiological pH (t(1/2) ~ 13-40 h). Meanwhile, the release of the first molecule of metronidazole from its twin esters 3a-d ensued rapidly in 80% human plasma (t(1/2) ~ 10-150 min) and in rat liver homogenate (t(1/2) ~ 4-55 min). The resulting hemiesters 2a-d showed a sustained release of the second molecule in the same biological fluids (t(1/2) ~ 3-9 h and 1-11 h respectively). In vivo evaluation studies of metronidazole and its twin esters 3a-d in mice and 3b in rabbits revealed that the prodrugs have been absorbed almost unhydrolyzed with considerable higher plasma level. Antiparasitic activity of the synthesized compounds was evaluated in mice against Giardia muris, the prodrug 3b showed improved antigiardial activity compared to the parent drug. These results suggest that the synthesized identical twin esters 3a-d may be useful as a promising new prodrug form of metronidazote for oral drug delivery.
- Mahfouz, Nadia M.,Aboul-Fadl, Tarek,Diab, Ahmed K.
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p. 675 - 683
(2007/10/03)
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- A new, modulated, oxidative ring cleavage of α-nitrocycloalkanones by Oxone: Synthesis of α,ω-dicarboxylic acids and α,ω-dicarboxylic acid monomethyl esters
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By the appropriate choice of the reaction conditions Oxone produces the ring cleavage of α-nitrocycloalkanones affording good yields of α,ω-dicarboxylic acids and α,ω-dicarboxylic acid monomethyl esters, respectively, regardless the ring size and/or the presence of an alkyl group as substituent.
- Ballini, Roberto,Curini, Massimo,Epifano, Francesco,Marcotullio, Maria Carla,Rosati, Ornelio
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p. 1049 - 1050
(2007/10/03)
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- Preparation of ω-hydroxy acids by reduction of α,ω-methylene diesters with NaBH4
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By reaction of the dicesium salts of long chain dicarboxylic acids (C atoms > 9) with methylene iodide the corresponding methylene diesters were prepared. These acylals, by reduction with NaBH4 in THF, give the corresponding ω-hydroxy acids.
- Benitez, Pilar,Delgado, Ana,Farrera, Joan-Anton,Ribo, Josep M.
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p. 1697 - 1702
(2007/10/03)
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- Rationalisation of the regioselective hydrolysis of aliphatic dinitriles with Rhodococcus rhodochrous AJ270
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Aliphatic dinitriles undergo regioselective hydrolysis with the title organism to give monoacids with up to four methylenes between the nitrile functions (optimally 2-3) or when either an oxygen is placed β, γ or δ to the nitrile (δ-placement being optimal) or β or γ (optimally γ) but not δ sulfur substituents are present; nitrogen substituents appear to behave as for oxygen but suffer a steric limitation of the size of the nitrogen substituent.
- Meth-Cohn, Otto,Wang, Mei-Xiang
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p. 1041 - 1042
(2007/10/03)
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- Regioselective biotransformations of dinitriles using Rhodococcus sp. AJ270
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A variety of dinitriles have been hydrolysed selectively under very mild conditions using Rhodococcus sp. AJ270. Aliphatic dinitriles NC[CH2]nCN 1 undergo regioselective hydrolysis to give the mono acids 2 with up to 4 methylenes between the nitrile functions while those with n > 4 give the diacids 3 in good yield. Dinitriles NC[CH2]nX[CH2]nCN 4 bearing an ether or sulfide linkage are efficiently transformed into the mono acids 5 when an oxygen is placed β, γ or δ to the cyano group or a β- or γ-sulfur is present. Hydrolysis of N,N-bis(2-cyanoethyl)anilines 4h-j takes place slowly affording exclusively the monoacids 5h-j while the monocyano amides 5o-p are obtained as the sole isolable product from rapid hydrolysis of the corresponding N,N-bis(2-cyanomethyl)butylamine 4o and N,N-bis(3-cyanopropyl)butylamine 4p. Higher homologues of arylimino- and butylimino-dinitriles are inert to enzymatic hydrolysis. A variety of other aliphatic dinitriles have been converted readily into mono acids in good to excellent yields except for o-phenylenediacetonitrile which gives o-phenylenediacetamide as the major product. The title organism also effects the hydrolysis of aromatic dinitriles with regiocontrol such as m- and p-dicyanobenzenes, but nct the ortho-substituted analogue. The scope and limitations of this enzymatic process have been systematically studied and the mechanism of regioselective hydrolysis has been discussed in terms of a chelation-deactivation effect.
- Meth-Cohn, Otto,Wang, Mei-Xiang
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p. 3197 - 3204
(2007/10/03)
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- Dealkylation of esters via treatment with N-(trimethylsilyl) diethylamine and methyl iodide
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A method for the conversion of esters to carboxylic acids has been reported. Reaction of methyl o-methoxybenzoate with N-(trimethylsilyl)diethylamine and methyl iodide, followed by hydrolysis, afforded o-methoxybenzoic acid with a 94% yield based on 96% conversion. Methyl esters of not only aromatic acids but also aliphatic acids were converted to the corresponding acids with high yields. A combination of N-(trimethylsilyl)dimethylamine and methyl iodide was also effective to give p-methylbenzoic acid with a 85% yield based on 90% conversion from the corresponding methyl ester.
- Yamamoto, Yasushi,Shimizu, Hideaki,Hamada, Yoshitaka
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p. 119 - 122
(2007/10/03)
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- Biopolymers derived from hydrolyzable diacid fats
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A monomeric diacid derivative includes at least two fatty acids coupled by a hydrolytically or enzymatically degradable bond. In a biological environment, the bond degrades forming naturally occurring fatty acid products thereby allowing elimination.
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- Production of carboxylic acids
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An improved process for the production of carboxylic acids and dicarboxylic acids by the catalytic oxidation of olefins and vicinal diols by hydrogen peroxide is provided. The process employs a rhenium (VII) catalyst, and a solvent comprising a mixture of a carboxylic acid or anhydride having 2 or more carbon atoms and a high boiling cyclic or acyclic ether. Particularly suitable carboxylic acids or anhydrides include acetic acid, propionic acid and acetic anhydride. Particularly suitable high-boiling ethers include 1,4-dioxane and diglyme.
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