- PROCESS FOR PRODUCTION OF DIOL ESTERS FROM ESTERS OF MONO ALCOHOLS
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Systems and methods of producing diol esters via coupling reactions are disclosed. A monohydric alcohol ester is used as the reactant in a coupling reaction to form a diol ester with or without the presence of a catalyst. Furthermore, the coupling reaction can be performed with or without mixing oxygen with the reactant. This method provides an additional or alternative pathway to produce diol esters other than direct esterification of diols.
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Paragraph 0047-0048
(2019/12/25)
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- Industrial method for preparing ethylene glycol diformate
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The invention relates to an industrial method for preparing ethylene glycol diformate (EGDF). The method comprises the following steps: completing esterification reaction of raw materials namely ethylene glycol and formic acid, in a composite solvent medium in the presence of an acid catalyst in an esterification reactor of a production device shown in drawings; and sequestially performing normalpressure desolventizing, reduced pressure low boiling removal and rectification treatment on esterification liquid, thereby obtaining the qualified EGDF. The ester content of the product is more thanor equal to 98%, the saponification value is 800-910mgKOH/g, and the product yield is more than 80%. Due to use of the composite solvent, the reaction temperature is decreased, and the reaction time is shortened. The distillation and rectification separation technology is utilized, and the esterification liquid after-treatment process is improved, so that the solvent and excessive formic acid canbe recycled. Therefore, the method disclosed by the invention has the advantages that the process is novel, the product quality is excellent, the yield is high, economic benefits are excellent, emission of three wastes is few and the method accords with the green chemical development direction.
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Paragraph 0015; 0016; 0017; 0020; 0021
(2018/05/16)
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- Synthesis method of glycol diformate
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The invention relates to a synthesis method of glycol diformate. The synthesis method is characterized in that butyl chloroformate and ethylene glycol are taken as raw materials, glycol diformate is generated through ester exchange under the action of a high-performance catalyst, and a by-product is ethylene glycol monoformate, and thus the synthesis method solves a problem that a conventional catalyst is difficult to react and has low yield. The mass fraction yield of glycol diformate is above 90%; glycol diformate is mild in reaction condition and high in yield, has no corrosion and environmental pollution, and is easy to separate and purify the product; the separation and purification process is simple and low in energy consumption; in a reaction process, raw materials can be reused, so that a production cost is saved; besides, with mature production technologies and abundance and cheap price of raw material resources, the synthesis method is convenient to achieve extensive industrialization production in the future.
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Paragraph 0027; 0028; 0029; 0030
(2017/10/11)
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- A glycol dimethyl ester synthesis process
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The invention relates to a method for preparing glycol diformate. The method comprises the following steps of (1) adding organic solvent, reactant glycol, 50% of formic acid aqueous solution (industrial formic acid) and an acid catalyst into a reactor and raising the temperature of a reaction system to divide water; and (2) collecting fraction with the temperature of 150-170 DEG C after a period of reaction time to obtain a glycol diformate product. The method is stable in reaction, safe, high in yield, low in cost, simple in process and easy to industrialize.
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Paragraph 0022; 0023
(2016/10/07)
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- Saturation vapor pressures and vaporization enthalpies of esters of ethylene glycol and lower carboxylic acids
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Saturation vapor pressures and vaporization enthalpies of ethylene glycol and C1-C5 carboxylic acid disubstituted esters of normal and branched structures are determined by the transfer method in the tem-perature range of 295 to 327 K. Dependences of vaporization enthalpies versus the number of carbon atoms in a molecule and the retention indices are determined. An analysis of existing calculation schemes is given to help predict the vaporization enthalpy of the compounds under study.
- Maslakova,Krasnykh,Levanova
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experimental part
p. 1695 - 1700
(2012/01/12)
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- Kinetics and mechanisms for the reactions of ozone with unsaturated oxygenated compounds
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Rate coefficients for the reaction of ozone with a series of unsaturated oxygenated compounds are determined in air at atmospheric pressure and (298±3) K. Rate data are obtained using both relative and absolute rate techniques, and the measured rate coefficients are found to be in good agreement. The results show that the reactivity of the compounds with respect to addition of ozone to the double bond is a function of the nature of the oxygenated substituent. Product distribution studies on the reactions provide information on the decomposition pathways for the primary ozonides, and on the effect of the oxygenated group on the relative importance of the degradation pathways. The results are discussed in terms of their importance in the atmospheric oxidation of unsaturated oxygenated compounds.
- Al Mulla, Ismael,Viera, Lisa,Morris, Rebecca,Sidebottom, Howard,Treacy, Jack,Mellouki, Abdelwahid
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experimental part
p. 4069 - 4078
(2011/09/30)
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- Low energy light-triggered oxidative cleavage of olefins
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A series of substituted olefins were tested for their reactivity with singlet oxygen as a singlet oxygen-mediated cleavable linker. Low intensity light of 200 mW/cm2 was irradiated to the solution of an olefin and 5,10,15-triphenyl-20-(4-hydroxyphenyl)-21H,23H-porphyrin under atmospheric condition. Among the tested olefins, 1,2-cis-diphenoxyethylene reacted fast with singlet oxygen, >80% within 15 min yielding a stoichiometric conversion to aldehyde product without any side reactions.
- Murthy, Rajesh S.,Bio, Moses,You, Youngjae
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scheme or table
p. 1041 - 1044
(2009/05/27)
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- Highly efficient formylation of alcohols, thiols and aniline derivatives by a heterogeneous (HCOOH/SiO2) system under microwave irradiation and solvent-free conditions
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A simple, rapid and efficient microwave-assisted procedure for the formylation of aniline derivatives and alcohols, using a heterogeneous (HCOOH/SiO2) system under solvent-free conditions is reported. The method is applied to a set of amines, alcohols and thiols and short reaction times (10 min) with high yields are reported. This protocol introduces a practical and viable green technology of solvent-free and catalyst-free reactions.
- Ghorbani-Vaghei, Ramin,Veisi, Hojat,Amiri, Mostafa,Chegini, Mohammad,Karimi, Mehdi,Dadamahaleh, Somayeh Akbari,Sedrpoushan, Alireza
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experimental part
p. 39 - 43
(2010/09/03)
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- Compounds, Compositions and methods for insect control
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Rapidly acting compositions having vapor phase insecticidal activity comprise natural products or natural product-based materials. Further, these materials are non-petroleum based, are typically 100% biodegradable, and typically do not persist in the environment, unlike traditional pesticides. The compositions kill susceptible insects on contact in seconds, even the notoriously hardy peripleneta species. The compositions also kill insects behind cracks and crevices and when sprayed onto absorbent surfaces such as wood and plasterboard, where traditional contact insecticides work poorly or not at all. New methods of testing insecticides can be used to quantify these effects.
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Page/Page column 12
(2008/06/13)
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- Azabicyclic-substituted fused-heteroaryl compounds for the treatment of disease
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The invention provides compounds of Formula I: wherein Azabicyclo is These compounds may be in the form of pharmaceutical salts or compositions, racemic mixtures, or pure enantiomers thereof. The compounds of Formula I are useful in pharmaceuticals in which α7 is known to be involved.
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- Quinuclidines-substituted-multi-cyclic-heteroaryls for the treatment of disease
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The invention provides compounds of Formula I: 1where in W is 2These compounds may be in the form of pharmaceutical salts or compositions, racemic mixtures, or pure enantiomers thereof. The compounds of Formula I are useful to treat diseases or conditions in which α7 is known to be involved.
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- Substituted 7-aza[2.2.1]bicycloheptanes for the treatment of disease
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The invention provides compounds of Formula I: which may be in the form of pharmaceutical acceptable salts or compositions, are useful in treating diseases or conditions in which α7 nicotinic acetylcholine receptors (nAChRs) are known to be involved.
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- Elucidation of the 1,4-dioxane decomposition pathway at discrete ultrasonic frequencies
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The sonolytic decomposition chemistry of the refractory compound 1,4-dioxane in aqueous solution has been investigated at four ultrasonic frequencies (205, 358, 618, and 1071 kHz). To maintain fully saturated solutions, argon and oxygen were used as sparge gases. Using a frequency of 358 kHz, the observed first-order kinetic rate constants for 1,4-dioxane destruction were highest with a sparge gas ratio of 75% Ar/25% O2 (k = 4.32 ± 0.31 x 10-4 s-1) and lowest in the presence of pure argon (k= 8.67 ± 0.47 x 10-5 s-1). Ethylene glycol diformate, methoxyacetic acid, formaldehyde, glycolic acid, and formic acid were found to be the major intermediates of 1,4-dioxane degradation. A reaction mechanism involving these byproducts was proposed concerning primarily reactions with oxidizing species (·OH, ·OOH, ·O) in and near the interfacial region of the cavitation bubble. The highest observed first-order 1,4-dioxane decomposition rate occurred at 358 followed by 618, 1071, and 205 kHz. At each frequency, approximately 85% of the initial carbon is accounted for as the parent compound, as an intermediate, or as CO2. The major byproducts formation was investigated at all four frequencies, and the results indicate that free radical mechanisms are significant over the entire range of frequencies studied. The sonolytic decomposition chemistry of the refractory compound 1,4-dioxane in aqueous solution has been investigated at four ultrasonic frequencies (205, 358, 618, and 1071 kHz). To maintain fully saturated solutions, argon and oxygen were used as sparge gases. Using a frequency of 358 kHz, the observed first-order kinetic rate constants for 1,4-dioxane destruction were highest with a sparge gas ratio of 75% Ar/25% O2 (k = 4.32 ± 0.31 × 10-4 s-1) and lowest in the presence of pure argon (k = 8.67 ± 0.47 × 10-5 s-1). Ethylene glycol diformate, methoxyacetic acid, formaldehyde, glycolic acid, and formic acid were found to be the major intermediates of 1,4-dioxane degradation. A reaction mechanism involving these byproducts was proposed concerning primarily reactions with oxidizing species (·OH, ·OOH, ·O) in and near the interfacial region of the cavitation bubble. The highest observed first-order 1,4-dioxane decomposition rate occurred at 358 followed by 618, 1071, and 205 kHz. At each frequency, approximately 85% of the initial carbon is accounted for as the parent compound, as an intermediate, or as CO2. The major byproducts formation was investigated at all four frequencies, and the results indicate that free radical mechanisms are significant over the entire range of frequencies studied.
- Beckett,Hua
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p. 3944 - 3953
(2007/10/03)
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- Ceric ammonium nitrate (CAN) - A useful catalyst for the rapid and high-yield esterification of carboxylic acids and alcohols with special reference to steroid and other multi-functional natural products
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Ceric ammonium nitrate (CAN) acts as a versatile catalyst for the esterification of carboxylic acids and alcohols, including steroids and other multi-functional natural products, in excellent yields under mild and convenient reaction conditions.
- Goswami,Chowdhury
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p. 955 - 957
(2007/10/03)
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- Kinetic and Product Study of the Atmospheric Photooxidation of 1,4-Dioxane and Its Main Reaction Product Ethylene Glycol Diformate
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A FTIR kinetic and product study of the OH-radical initiated oxidation of 1,4-dioxane (DOX) has been performed in a quartz-glass photoreactor in the laboratory under different conditions and also in the outdoor EUPHORE simulation chamber in Valencia, Spain. Using the relative kinetic technique, a rate coefficient of k = (1.24 ± 0.04) × 10-11 cm3 molecule-1 s-1 was determined for the reaction at 298 K in 1000 mbar of synthetic air, which is in good agreement with other published values. The major reaction product both in the presence and absence of NO was ethylene glycol diformate (EDF). This compound has been synthesized, and authentic samples have been used for calibration. Integrated band intensities have been calculated for the three strongest bands of EDF: (4.99 ± 0.06) × 10-17 cm molecule-1 for 1100-1225 cm-1, (3.90 ± 0.05) × 10-17 cm molecule-1 for 1670-1820 cm-1, (9.34 ± 0.11) × 10-18 cm molecule-1 for 2775-3075 cm-1. In the laboratory reactor, yields for EDF of 87 ± 9 and 95 ± 10 mol % were obtained using the photolysis of MeONO/NO/air and H2O2/NO/air as the OH radical sources, respectively. Using only the photolysis of H2O2/ air as the OH source resulted in a molar yield of 55 ± 6 mol % for EDF. In the outdoor EUPHORE simulation chamber a yield of 95 ± 10 mol % was obtained from irradiation of a DOX/NOx/air mixture. The OH-radical- and Cl-atom-initiated oxidation of EDF has also been investigated. Rate coefficients of kOH = (4.72 ± 0.31) × 10-13 cm3 molecule-1 s-1 and kcl = (3.52 ± 0.09) × 1012 cm3 molecule-1 s-1 have been determined for the reaction of EDF with OH radicals and Cl atoms, respectively, at 298 K and 1000 mbar total pressure. The products determined in the Cl-initiated oxidation in the presence of NOx were formic acid anhydride (FAA), formic acid (FA), and carbon monoxide (CO) with yields of 173 ± 34 mol %, 45 ± 9 mol %, and 41 ± 8 mol %, respectively. Formation of a peroxy formyl nitrate was also observed. In the absence of NOx the yields of FAA, FA and CO were 144 ± 29 mol %, 39 ± 8 mol %, and 22 ± 4 mol %, respectively.
- Maurer, Tobias,Hass, Heinz,Barnes, Lan,Becker, Karl H.
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p. 5032 - 5039
(2007/10/03)
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- Mechanism of the degradation of 1,4-dioxane in dilute aqueous solution using the UV/hydrogen peroxide process
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1,4-Dioxane is an EPA priority pollutant often found in contaminated groundwaters and industrial effluents. The common techniques used for water purification are not applicable to 1,4-dioxane, and the currently used method (distillation) is laborious and expensive. This study aims to understand the degradation mechanism of 1,4-dioxane and its byproducts in dilute aqueous solution toward complete mineralization, by using the UV/H2O2 process in a UV semibatch reactor. The decay of 1,4-dioxane generated several intermediates identified and quantified as aldehydes (formaldehyde, acetaldehyde, and glyoxal), organic acids (formic, methoxyacetic, acetic, glycolic, glyoxylic, and oxalic) and the mono- and diformate esters of 1,2- ethanediol. Measurement of the total organic carbon (TOC) during the treatment indicated a good agreement between the experimentally determined TOC values and those calculated from the quantified reaction intermediates, ending in complete mineralization. A reaction mechanism, which accounts for the observed intermediate products and their time profiles during the treatment, is proposed. Considering the efficacy of the 1,4-dioxane removal from dilute aqueous solutions, as shown in this work, the present study can be regarded as a model for industrially affordable Advanced Oxidation Technologies. 1,4-Dioxane is an EPA priority pollutant often found in contaminated groundwaters and industrial effluents. The common techniques used for water purification are not applicable to 1,4-dioxane, and the currently used method (distillation) is laborious and expensive. This study aims to understand the degradation mechanism of 1,4-dioxane and its byproducts in dilute aqueous solution toward complete mineralization, by using the UV/H2O2 process in a UV semibatch reactor. The decay of 1,4-dioxane generated several intermediates identified and quantified as aldehydes (formaldehyde, acetaldehyde, and glyoxal), organic acids (formic, methoxyacetic, acetic, glycolic, glyoxylic, and oxalic) and the mono- and diformate esters of 1,2-ethanediol. Measurement of the total organic carbon (TOC) during the treatment indicated a good agreement between the experimentally determined TOC values and those calculated from the quantified reaction intermediates, ending in complete mineralization. A reaction mechanism, which accounts for the observed intermediate products and their time profiles during the treatment, is proposed. Considering the efficacy of the 1,4-dioxane removal from dilute aqueous solutions, as shown in this work, the present study can be regarded as a model for industrially affordable Advanced Oxidation Technologies.
- Stefan, Mihaela I.,Bolton, James R.
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p. 1588 - 1595
(2007/10/03)
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- Products of the gas-phase reactions of the OH radical with 1-methoxy-2-propanol and 2-butoxyethanol
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Glycol ethers are used as solvents and are hence liable to b;e released to the atmosphere, where they react and contribute to the formation of photochemical air pollution. In this work, products of the gas-phase reactions of the OH radical with 1-methoxy-2-propanol and 2-butoxyethanol in the presence of NO have been investigated at 298 ± 2 K and 740 Torr total pressure of air by gas chromatography, in situ Fourier transform infrared spectroscopy, and in situ atmospheric pressure ionization tandem mass spectrometry. The products observed from 1-methoxy-2-propanol were methyl formate, methoxyacetone, and acetaldehyde with molar formation yields of 0.59 ± 0.05, 0.39 ± 0.04, and 0.56 ± 0.07, respectively. The products observed and quantified from 2-butoxyethanol were n-butyl formate, 2-hydroxyethyl formate, propanal, 3-hydroxybutyl formate, and an organic nitrate (attributed to CHsChbCHaCH2OCH(ON02)CH2OH and its isomers), with molar formation yields of 0.57 ± 0.05, 0.22 ± 0.05, 0.21 ± 0.02, 0.07 ± 0.03, and 0.10 ± 0.03, respectively. An additional product of molecular weight 132, attributed to one or more hydroxycarbonyl products, was also observed from the 2-butoxyethanol reaction by atmospheric pressure ionization mass spectrometry. For both glycol ethers, the majority of the reaction products and reaction pathways are accounted for, and detailed reaction mechanisms are presented which account for the observed products.
- Tuazon, Ernesto C.,Aschmann, Sara M.,Atkinson, Roger
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p. 3336 - 3345
(2007/10/03)
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- An improved method for preparing ethylene glycol diformate
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An improved procedure was developed for preparing high-purity ethylene glycol diformate by acylation of ethylene glycol with formic acid.
- Kukharev,Stankevich,Klimenko,Podkuiko
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p. 2045 - 2046
(2007/10/03)
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- Atmospheric chemistry of 1,4-dioxane. Laboratory studies
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A pulse radiolysis technique was used to measure the UV absorption spectra of c-C4H7O2 and (c-C4H7O2)O2 radicals over the range 220-320 nm, σ(c-C4H7O2)250 nm = (5.9 ± 0.6) × 10-18 and σ[(c-C4H7O2)O2]240 nm = (4.8 × 0.8) × 10-18 cm2 molecule-1. The observed self-reaction rate constants for the c-C4H7O2 and (c-C4H7O2)O2 radicals, defined as -d[c-C4H7O2]/dt = 2k4[c-C4H7O2]2 and -d[(c-C4H7O2)O2]/dt = 2k5 obs[(c-C4H7O2)O2]2 were k4 = (3.3 ± 0.4) × 10-11 and k5 obs = (7.3 ± 1.2) × 10-12 cm3 molecule-1 s-1. The rate constants for reactions of (c-C4H7O2)O2 radicals with NO and NO2 were k6 (1.2 ± 0.3) × 10-11 and k7 = (1.3 ± 0.3) × 10-11 cm3 molecule-1 s-1, respectively. The rate constants for the reaction of F atoms with 1,4-dioxane and the reaction of c-C4H7O2 radicals with O2, were k3 = (2.4 ± 0.7) × 10-10 and k2 = (8.8 ± 0.9) × 10-12 cm3 molecule-1 s-1, respectively. A relative rate technique was used to measure the rate constant for the reaction of Cl atoms with 1,4-dioxane, k17 = (2.0 ± 0.3) × 10-10 cm3 molecule-1 s-1. A long-pathlength FTIR spectrometer coupled to a smog chamber system was used to show that the sole atmospheric fate of the alkoxy radical (c-C4H7O2)O is decomposition via C-C bond scission leading to the formation of H(O)COCH2CH2OC(O)H (ethylene glycol diformate).
- Platz,Sehested,Mogelberg,Nielsen,Wallington
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p. 2855 - 2863
(2007/10/03)
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- Oxidation vs. fragmentation in radiosensitization. Reactions of α-alkoxyalkyl radicals with 4-nitrobenzonitrile and oxygen. A pulse radiolysis and product analysis study
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α-Monoalkoxyalkyl radicals produced from 1,4-dioxane (100percent), 1,3-dioxane (56percent), tetrahydrofuran (92percent) and dimethyl ether (100percent) by H-abstraction by hydroxyl radicals generated in the radiolysis of water were found to react with 4-nitrobenzonitrile (NBN) by addition to give N-alkoxyaminoxyl-type radicals, which have absorption maxima at about 310 nm and decay very slowly (k = 0.4 - 1.0 s-1).On the other hand, the reaction of the α-dialkoxyalkyl radical, 1,3-dioxan-2-yl 3 with NBN leads to the rapid formation of the radical anion NBN.The N-alkoxyaminoxyl-type radicals (A in the case of 1,4-dioxane and D in the case of dimethyl ether) react with ascorbate (k ca. 2*104 dm3 mol-1 s-1).They have a very low reactivity with oxygen (k 3 dm3 mol-1 s-1 in the case of tetrahydrofuran).On the other hand, they are rapidly reduced by NBN radical anion (k ca. 109 dm3 mol-1 s-1 as observed with A and with B derived from 1,3-dioxane).The products -7 mol J-1> in the γ-radiolysis of N2O-saturated solution of 1,4-dioxane in the presence of NBN are 1,4-dioxan-2-one (0.3), 2-hydroxy-1,4-dioxane (2.5), ethane-1,2-diol monoformate (2.1), ethane-1,2-diol diformate (0.7), formaldehyde (2.1), 4-nitrosobenzonitrile and other reduction products of 4-nitrobenzonitrile.These products are accounted for as resulting from the fragmentation of the aminoxyl radical A by (a) heterolysis of the C-O bond (45percent leading to the one-electron oxidation of the 1,4-dioxan-2-yl radical) and (b) homolysis of the N-O bond (55percent leading to the formation of the 1,4-dioxan-2-oxyl radical which undergoes further fragmentation.The products from the reaction of methoxymethyl radicals with NBN under γ-radiolysis conditions are formaldehyde (5.7), methanol (2.5) and methyl formate (1.3).It is concluded that also in this case the decay of the aminoxyl radical D occurs by two pathways: the heterolysis route (46percent) and the homolysis route (54percent).In the presence of oxygen the 1,4-dioxan-2-yl radicals are converted into the corresponding peroxyl radicals.Their bimolecular decay (2k = 2.0*108 dm3 mol-1 s-1) yields the same products as in the case of NBN (albeit with a different product distribution and the formation of some peroxides): 1,4-dioxan-2-one (0.4), 2-hydroxy-1,4-dioxane (0.4), ethane-1,2-diol monoformate (0.6), ethane-1,2-diol diformate (2.8) and formaldehyde (0.6).These results indicate that fragmentation reactions involving the carbon-skeleton of organic radicals are important not only in the case of peroxyl radicals but they can also be induced by nitroaromatic sensitizers.In cells, reduction of the long-lived sensitizer adduct radicals by reducing agents such as ascorbate to give (toxic) hydroxylamine type products may compete with the homolytic or heterolytic fragmentation of the N-alkoxyaminoxyl radicals.
- Nese, Chandrasekhar,Schuchmann, Man Nien,Steenken, Steen,Sonntag, Clemens von
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p. 1037 - 1044
(2007/10/02)
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- Ethylene Oxide-mediated Reduction of CO2 to CO and Ethylene Glycol catalysed by Ruthenium Complexes
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In the presence of ethylene oxide, CO2 is efficiently hydrogenated to give CO and ethylene glycol in good yields using ruthenium complexes as homogeneous catalysts.
- Tominaga, Ken-ichi,Sasaki, Yoshiyuki,Watanabe, Taiki,Saito, Masahiro
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p. 1489 - 1490
(2007/10/02)
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- Hydration of Alkynes in Anhydrous Medium with Formic Acis as Water Donor
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Formic acid has been found to hydrate alkynes in the absence of water to give oxo products and carbon monoxide.The scope of the reaction of alkynes and formic acid has been delineated.Hydrocarbon alkynes were found to be reactive in the absence of catalyst.Functionalized alkynes, in particular oxygenated alkynes, are inert toward formic acid but can be activated catalytically with Ru3(CO)12.Consequently, all the tested types of alkynes were found to give oxo products and CO with formic acid.The mechanism of the reaction was examined.With some alkynes, the primary oxo products underwent secondary reactions that gave rise to unexpected products.
- Menashe, Naim,Shvo, Youval
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p. 7434 - 7439
(2007/10/02)
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- Synthesis and structure of tetrahydropyrano[2,3-b]-[1,4]dioxines
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Under acidic conditions the 6-methoxypyranone 5 and 1,2-ethanediol are converted via the dioxolane 6 to the tetrahydro-cis-pyranodioxinone 7-cis. When 5 is treated with 2-mercaptoethanol and base the thioether 10 is isolated. Acid induced cyclisation of 10 yields the cis- and trans-tetrahydropyrano-oxathiinones 11-cis and 11-trans. Trans-1,2-cyclohexanediol (12) reacts with 5 to the dioxolane derivatives 13 and 14, which can be transformed to the octahydro-trioxa-anthracene derivatives 15 and 16. The 1H-NMR data show that configuration and conformation of 6 and 7 are in accordance with the pyranodioxane structure in 13 and 15.
- Wunsch,Eiden
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- The preparation of esters of formic acid using boron oxide
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Boron oxide has been found to act as an efficient reagent in the preparation of a number of formate esters by the direct esterification of formic acid with the alcohol.The reaction is most appropriate for primary and secondery alcohols, including unsaturated alcohols.The formate ester so produced is free of contamination by unreacted alcohol.
- Carlson, Charles G.,Hall, Judith E.,Huang, Yan Y.,Kotila, Sirpa,Rauk, Arvi,Tavares, Donald F.
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p. 2461 - 2463
(2007/10/02)
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- PREPARATIVE UV-VIS LASER PHOTOCHEMISTRY: MOLECULAR OXYGEN TRAPPING OF THE PATERNO-BUECHI TRIPLET DIRADICALS DERIVED FROM 1,4-DIOXENE.
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Argon ion laser irradiation of CCl4 solutions of 1,4-dioxene and bezophenone or p-benzoquinone under oxygen pressure affords the 1,2,4-trioxanes 4a,b (cis ring junction by NOE 1H-NMR differential spectroscopy), resulting from trapping of the corresponding triplet preoxetane diradicals.
- Adam, Waldemar,Kliem, Ulrike,Lucchini, Vittorio
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p. 2953 - 2956
(2007/10/02)
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