Journal articles: 'Butyl phenyl ether'

1

Campanella, Enrique A. "Infinite-dilution activity coefficients of organic solutes in methyl phenyl ether, butyl ether and methyliso-butyl ketone." Chemical Engineering & Technology 14, no. 6 (December 1991): 376–78. http://dx.doi.org/10.1002/ceat.270140603.

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Abid, Mohammad Fadhil, Mohammad Ibrahim, and Ahlam Saaid. "Improvement of Antiknocking Characteristics of Iraqi Gasoline." Journal of Petroleum Research and Studies 4, no. 1 (June 1, 2013): 10–26. http://dx.doi.org/10.52716/jprs.v4i1.80.

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Tetraethyl lead (TEL), which is a common additive to the Iraqi pool gasoline, is usually classified- among the most toxic selective additive even when it is added at low doses (~ 1.5-2.0 %v/v). The present work was devoted to prepare and investigate the effect of phenyl tert-butyl ether as an alternative selective additive to the Iraqi pool gasoline produced in Doura Refinary-Midland Refineries Co. Comparing with other additives-except TEL-, it was found that phenyl tert-butyl ether increased RON of Doura pool gasoline by (5.7 to 10%) at a dose of 5%v/v and it increased RON by (4.5 to 11.9%) at a dose of 8%v/v. Moreover, it appears to have no adverse human health effects which make the suggested additive promising for increasing the anti-knocking characteristic of Iraqi gasoline.

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3

Kondrat, Richard W., and Thomas Hellman Morton. "Sterochemical differntiation in decomposition ofsec-butyl phenyl ether molecular ions." Organic Mass Spectrometry 23, no. 7 (July 1988): 555–57. http://dx.doi.org/10.1002/oms.1210230711.

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4

Schaefer, Ted, Kerry J. Cox, Cherrie L. Morier, Christian Beaulieu, Rudy Sebastian, and Glenn H. Penner. "Motion about the bond in benzyl OR (R = CH3, CH2CH3, CH(CH3)2, C(CH3)3). Solvent and substituent dependence." Canadian Journal of Chemistry 68, no. 9 (September 1, 1990): 1553–58. http://dx.doi.org/10.1139/v90-240.

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The 1H nuclear magnetic resonance spectral parameters of benzyl alkyl ethers (CH3, CH2CH3, CH(CH3)2, and C(CH3)3) in CS2 and acetone-d6 solutions are obtained, as are those for the 3,5-dichloro derivatives (CH3, CH2CH3, and CH(CH3)3) in acetone-d6 solution. The long-range coupling constants between the methylene and para ring protons show that the apparent twofold barrier to rotation about the [Formula: see text] bond is solvent and ring-substituent dependent. The apparent twofold barrier ranges from a vanishing value for benzyl methyl ether in CS2 solution to as much as 4.6 kJ/mol for 3,5-dichlorobenzyl isopropyl ether in acetone-d6 solution. The data imply that, for the free molecules, the conformation of highest energy has the CH2—O bond in a plane perpendicular to that of the phenyl group. Molecular orbital computations with a minimal Gaussian basis set agree that, for benzyl methyl ether in the exo form (the methyl group pointing away from the phenyl moiety), this conformation is the least stable. However, geometry optimization procedures imply that the CH2—O bond is twisted out of the ring plane by 30.3° in the most stable geometry of the exo form. Such procedures for the (distorted) endo form locate another stable conformer, in which the CH2—O bond is twisted out of the phenyl plane by 45°, only 0.25 kJ/mol less stable than the most stable conformer of the exo form. These results, together with some computations for the tert-butyl derivative, are discussed in terms of the theoretical potentials for rotation about the [Formula: see text] bond. The approximate potential surface is rather flat compared to kT at ambient temperatures for the free molecules, consistent with its sensitivity to the medium and to ring substituents. Keywords: 1H NMR, benzyl alkyl ethers; long-range coupling constants in benzyl alkyl ethers; conformations, benzyl alkyl ethers; internal motion, benzyl alkyl ethers; MO computations on benzyl methyl ether.

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Baker, MV, C. Ghitgas, RJ Dancer, RK Haynes, and GV Sherwood. "The Conversion of Ethyl Dienol Ether and Dienyl Pivalate Derivatives of Hagemanns Ester Into Bicyclic Enones." Australian Journal of Chemistry 40, no. 8 (1987): 1331. http://dx.doi.org/10.1071/ch9871331.

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The cyclization of compounds obtained from ethyl dienol ether and dienyl pivalate derivatives of Hagemann's ester has been examined. The carbanions of methyl phenyl sulfone and methyl phenyl sulfoxide react with the methylated dienol ether (4) to give the β-keto sulfone (8) and sulfoxide (9), the former of which was converted into the oxabicyclo[4.3.0]non-1-en-3-one (16). The iodide (17) with potassium t-butoxide in t-butyl alcohol gave the octahydronaphthalenone (18). With lithium ethoxide in tetrahydrofuran the octahydronaphthalenedione (22) was obtained from the dienyl pivalate (24). Both reactions involve the generation and intramolecular cyclization of a dienolate produced by cleavage of the pivaloyl group in each of (17) and (24). The scope and limitations of these reactions are briefly discussed.

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Journal, Baghdad Science. "Construction of Phenytoin Selective Electrodes and Its Application to Pharmaceutical Preparation." Baghdad Science Journal 7, no. 1 (March 7, 2010): 687–95. http://dx.doi.org/10.21123/bsj.7.1.687-695.

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Phenytoin selective electrodes were constructed based on penytoin-phosphotungstate (Ph-PT) complex with different plasticizers; di-butyl phosphate (DBP), tri-butyl phosphate (TBP), di-butyl phthalate (DBPH),and o-nitro phenyl octyl ether (NPOE) phthalate. The electrodes based on DBPH, ONPOE plasticizers gave Narnistain slope which are, 56.4 and 55.3mV/decade with detection limit of 1.9x10-5 M , 1.8x10-5 and concentration range 10-1 to 10-4 M and pH range 3.0 – 8.0. The electrodes based on TBP and DBP showed non-Nernistain slopes, 40.2,40.5 mV/decade for both plasticizers. Interfering of some cations was investigated and shows no interfering with electrodes response. Potentiometric methods were used for measuring phenytion in pharmaceutical drugs (tablets) and the electrode based on DBPH was used for determination. The recovery obtained from measuring was in good agreements with that given in British Pharmacopeias.

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7

Lajunen, Martti, Kirsi Tanskanen-Lehti, Markus Koskenlinna, Lauri Niinistö, Dagfinn W. Aksnes, Jan Balzarini, Bengt Fransson, Ulf Ragnarsson, and George W. Francis. "Acid-Catalyzed Hydrolysis of tert-Butyl Phenyl Ether. An Application of the Excess Acidity Method." Acta Chemica Scandinavica 48 (1994): 861–64. http://dx.doi.org/10.3891/acta.chem.scand.48-0861.

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8

Yoshioka, Aki, Teruyuki Seino, Masayoshi Tabata, and Mitsuo Takai. "Homolytic Scission of Interunitary Bonds in Lignin Induced by Ultrasonic Irradiation of MWL Dissolved in Dimethylsulfoxide." Holzforschung 54, no. 4 (July 4, 2000): 357–64. http://dx.doi.org/10.1515/hf.2000.062.

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SummaryAn electron spin resonance (ESR) method combined with a spin trapping technique was applied to trap and characterize unstable radicals which were generated by ultrasonic irradiation of the dimethylsulfoxide (DMSO) solution of a softwood, Yezo Spruce (Picea jezoensiscarr.) lignin. It was found that an unstable secondary carbon radical, ~CH • in the solution was trapped as the stable nitroxide spin adduct when the DMSO solution was subjected to ultrasonic irradiation in the presence of a spin trapping reagent: 2,4,6-tri-tert-butylnitrosobenzene (BNB) at 50°C for 30 min. This means that the alkyl phenyl ether bonds, ~CH-O-phenyl, known as interunitary bonds in lignins were homolytically cleaved by the ultrasonic irradiation, although the phenoxy radical Ph-O •, called guaiacoxy radical, i.e. the counter radical of the secondary carbon radical, was not trapped by the BNB spin trap. This suggests that the trapping of the guaiacoxy radical, having a methoxy group in anortho-position, by the BNB molecule, carrying two bulky butyl groups in theortho-positions, is sterically hindered.

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9

Pajuste, Karlis, Aiva Plotniece, Kintija Kore, Liva Intenberga, Brigita Cekavicus, Dainis Kaldre, Gunars Duburs, and Arkadij Sobolev. "Use of pyridinium ionic liquids as catalysts for the synthesis of 3,5-bis(dodecyloxycarbonyl)-1,4-dihydropyridine derivative." Open Chemistry 9, no. 1 (February 1, 2011): 143–48. http://dx.doi.org/10.2478/s11532-010-0132-x.

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AbstractThe synthesis of cationic amphiphilic 1,4-dihydropyridine derivative, potential gene delivery agent is achieved via an efficient multi-step sequence. The key step of this approach is a two-component Hantzsch type cyclisation of 3-oxo-2-[1-phenylmethylidene]-butyric acid dodecyl ester and 3-amino-but-2-enoic acid dodecyl ester utilising bis(2-hydroxyethyl)ether as a solvent and 1-butyl-4-methylpyridinium chloride as a catalyst. The 1,4-dihydropyridine derivative with long alkyl ester chains at positions 3 and 5 of the 1,4-DHP ring — 3,5-bis(dodecyloxycarbonyl)-2,6-dimethyl-4-phenyl-1,4-dihydropyridine was obtained in substantially higher yield with respect to classical Hantzsch synthesis. Bromination of this compound followed by nucleophilic substitution of bromine with pyridine gave the desired cationic amphiphilic 1,4-dihydropyridine.

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10

Lu, Chun Yan, and Guo Rong Cao. "Preparation and Characterization of Fluorinated Acrylate Copolymer Emulsion." Applied Mechanics and Materials 731 (January 2015): 541–46. http://dx.doi.org/10.4028/www.scientific.net/amm.731.541.

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A fluorinated acrylate copolymer emulsion with core-shell structure was synthesized by semi-continuous emulsion polymerization using methyl methacrylate (MMA ), butyl acrylate (BA) as the raw material, hexafluorobutyl methacrylate as fluorinated acrylate monomer, ammonium persulfate (APS) as initiator, sodium dodecyl sulfate (SDS) and polyoxyethylene octyl phenyl ether (OP-10) as emulsifier and taking water as dispersion medium. The as-prepared latexes are characterized by Fourier transforms infrared (FT-IR) spectroscopy. The hydro-oleophobic of copolymer is determined by contact angle meter. The typical core-shell structure is proved by differential scanning calorimetry (DSC). The results show that the copolymer emulsion has good hydro-oleophobic when the content of hexafluorobutyl methacrylate is 15%, used the delay loading method, the water contact angle of the coating surface is 104 °, the hexadecane contact angle is 75 °. Key words: fluorinated acrylate; copolymer; emulsion; hydro-oleophobic; contact angle

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11

Litwinienko, Grzegorz, Gino A. DiLabio, and K. U. Ingold. "A theoretical and experimental investigation of some unusual intermolecular hydrogen-bond IR bands — Appearances can be deceptive." Canadian Journal of Chemistry 84, no. 10 (October 1, 2006): 1371–79. http://dx.doi.org/10.1139/v06-097.

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The IR spectra of the O-H stretch for hydrogen bonds (HBs) arising from complex formation between the HB donor (HBD), 4-fluorophenol, and the HB acceptors, peroxides and ethers, frequently show asymmetry that appears to arise from two incompletely resolved bands from two different complexes, but the O-H HB bands with the HBD methanol are symmetric (M. Berthelot, F. Bessau, and C. Laurence. Eur. J. Org. Chem. 925 (1998)). The present studies show that this difference in O-H HB band shapes also is true for other phenols and alcohols. However with ethylene oxide, 4-fluorophenol gives an almost symmetric O-H HB band with a very broad maximum, while alcohols give symmetric O-H HB bands with well-defined maxima. It is shown by experiment that the unusual O-H HB band shapes for the phenols are not due to Fermi resonance and are unrelated to the enthalpies of HB complex formation. Theoretical exploration of the potential energy (PE) surfaces for complexes of 4-fluorophenol and methanol with tert-butyl methyl ether and ethylene oxide reveals that O-H HB band asymmetry or broadness cannot be ascribed to the presence of two different HB complexes. For this ether, the PE surfaces for rotation about the HB and for up-and-down motion of the HBD with respect to the COC plane of the ether are relatively symmetric for methanol, but are strongly asymmetric for 4-fluorophenol, hence the differences in the O-H HB band shapes. The PE surfaces for the epoxide are effectively symmetric, but the PE for rotation about the HB has a single broad minimum for methanol, whereas with 4-fluorophenol there are two minima owing to attractive interactions between the phenyl group and the CH2 groups of the epoxide. The previously unknown β2H values for ethylene oxide and tetramethylethylene oxide are 0.36 and 0.58, respectively.Key words: asymmetric IR O-H bands, asymmetric potential energy surfaces, hydrogen-bonded complexes, hydrogen bond enthalpy, O-H frequency shift.

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12

Hsiao, Hsu-Chin, Wei-Chi Li, and Hung-Shan Weng. "A preliminary evaluation of a continuous-flow reactor for liquid-liquid-solid phase-transfer catalyzed synthesis ofn-butyl phenyl ether." Journal of Chemical Technology & Biotechnology 80, no. 3 (2005): 299–306. http://dx.doi.org/10.1002/jctb.1151.

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13

Guo, Hai-Qing, Atsushi Kajiwara, Yotaro Morishima, Mikiharu Kamachi, and Wolfram Schnabel. "Polymerization of n-Butyl Vinyl Ether Photoinitiated by the Initiator System Poly(methyl phenyl silane)/N-Ethoxy-2-methylpyridinium Iodide/ZnI2/Benzaldehyde." Polymer Journal 29, no. 5 (May 1997): 446–49. http://dx.doi.org/10.1295/polymj.29.446.

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14

Nemati, Nasrin, Reza Eslamloueyan, Amalie Modvig, and Anders Riisager. "Pd-Catalyzed Cyclocarbonylation of Allylic Alcohol under Benign Conditions with Ionic Liquid as Stabilizer." Materials 13, no. 9 (May 1, 2020): 2093. http://dx.doi.org/10.3390/ma13092093.

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Homogeneous palladium-catalyzed (Pd-catalyzed) cyclocarbonylation of unsaturated allylic alcohols and alkynols in the presence of hydrogen forms lactone products with important applications in the food, perfume, and polymer industry. In this work, the cyclocarbonylation of 2-methyl-3-buten-2-ol was studied for the first time using a very active Pd-DPEphos (bis[(2-diphenylphosphino)phenyl]ether) catalyst in the presence of the ionic liquid (IL) [BMIM]Cl (1-butyl-3-methylimidazolium chloride) in dichloromethane to selectively produce 4,4-dimethyl-γ-butyrolactone. The effect of different parameters such as temperature, gas partial pressures, time of reaction, substrate and ligand concentrations were investigated and found to provide optimal conditions for lactonization (95 °C, 28 bar (CO/H2/N2: 20/5/3)), 18 h, 0.1 M substrate, and 16 mol% DPEphos), which were significantly milder than previously reported systems for cyclocarbonylation. Importantly, the study further showed that presence of the IL in the reaction mixture provided stabilization of the catalyst system and prevented formation of Pd-black, which allowed reuse of the catalytic system in consecutive reactions after intermediate extraction of the lactone product.

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15

Muralikrishna Ramisetti, Lakshmana Rao Atmakuri, and Rama Shekara Reddy Dachuru. "Determination of obeticholic acid and its glycine conjugate in human plasma using liquid chromatography-tandem mass spectrometry." International Journal of Research in Pharmaceutical Sciences 11, SPL4 (December 21, 2020): 2681–87. http://dx.doi.org/10.26452/ijrps.v11ispl4.4540.

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A sensitive and selective liquid chromatography/tandem mass spectrometry method was recommended by the authors for the determination orally bioavailable farnesoid X receptor agonist obeticholic acid along with its glycine conjugate glycoobeticholic acid human plasma. Obeticholic acid_d5 and glycoobeticholic acid_d5 were used as internal standards, respectively. After extraction with a mixture of tert-butyl methyl ether and dichloromethane, samples were separated on a phenyl column with a mobile phase of 2mM ammonium acetate with 0.01% formic acid and methanol (15:85, v/v). Analysis was performed on an AB Sciex 4500 triple quadrupole mass spectrometer and data acquisition was performed by multiple reaction monitoring (MRM) in the negative ionization mode. Obeticholic acid and its conjugate were quantified in the linearity range of 0.50-100.00 ng/mL and the correction coefficients were≥0.99 during the validation. Precision and accuracy in different days (inter-day) and single day (intra-day) were meeting the acceptance criteria specified in the recent US FDA bioanalytical method validation guidelines. A variety of stability experiments in neat samples and plasma samples were conducted and the results are meeting the acceptance criteria. A run time of 2.5 min for each sample made it possible to analyze a greater number of samples in a short time, thus increasing productivity. This method could be useful to quantitate obeticholic acid and glycoobeticholic acid in real clinical samples.

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16

Walker, James A., and Wing Tsang. "Single-pulse shock tube studies on the thermal decomposition of n-butyl phenyl ether, n-pentylbenzene, and phenetole and the heat of formation of phenoxy and benzyl radicals." Journal of Physical Chemistry 94, no. 8 (April 1990): 3324–27. http://dx.doi.org/10.1021/j100371a023.

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17

Hsiao, Hsu-Chin, and Hung-Shan Weng. "Synthesis ofn-butyl phenyl ether by tri-liquid-phase catalysis using poly(ethylene glycol)-600 as a catalyst - analysis of factors affecting the reaction in a batch reactor." Journal of Chemical Technology & Biotechnology 76, no. 9 (2001): 959–65. http://dx.doi.org/10.1002/jctb.470.

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18

Ikhsanov, Y. S., G. E. Tasmagambetova, Y. A. Litvinenko, G. Sh Burasheva, and G. A. Seitimova. "PHYTOCHEMICAL COMPOSITION OF LIPOPHILIC FRACTION OF PLANTS OF THE PLANT ROSA CANINA L. GENUS ROSA." SERIES CHEMISTRY AND TECHNOLOGY 2, no. 440 (April 15, 2020): 69–74. http://dx.doi.org/10.32014/2020.2518-1491.25.

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The genus of wild rose, or Rosa L., belongs to the family Rosaceae. It has many cultural forms, bred under the general name Rosa. At the moment, more than 400 species of rose hips are known. Usually these are upright shrubs, less often creepers, sometimes low tree-like forms or almost herbaceous plants. Rosehip is common in the temperate and subtropical zones of the Northern Hemisphere, it can often be found in the mountainous regions of the tropical zone. Some species of rose hips are common from the Arctic Circle in the north to Ethiopia in the south. On the American continent - from Canada to Mexico, Favorable conditions for Rosehip are in the Mediterranean region. Several species of the Rosehip genus have an extensive distribution area. Kazakhstan has significant resources of medicinal raw materials of plant origin. Among the most priority representatives of the wild flora are species of the rosehip genus - Rosa L. as a most valuable medicinal plant. In total, 21 species of wild rose grow in the republic, including 5 in the central Kazakhstan: R. glabrifolia - sh. naked, R. laxa Retz. - w. loose, R. acicularis Lindl. - (W. needlefish), R. majalis Herrm. (R. cinnamomea L.) - sh. May (W. cinnamon) and R. pimpinellifolia L. (R. spinosissima L.) - W. femoral cell. Kazakhstan species of the genus Rosa L. Rose hips are characterized by a high content of biologically active substances and are widely used both in medicine and in cooking. In this paper, a comparative analysis of rose hips, Rosa canina L., harvested in the fall of 2018 is carried out. Plant raw materials are collected in the southern region of the Republic of Kazakhstan (Almaty region). The crushed air-dry raw materials were extracted with hexane and chloroform in the ratio of raw materials-reagent (1:10) in a Soxhlet apparatus. The resulting extract was concentrated under mild conditions to a thick concentrate, which was analyzed on a gas chromatograph with a mass selective detector. The analyzes were carried out on a gas chromatograph with a mass spectrometric detector 6890N / 5973C (Agilent, USA). The peaks detected in the chromatograms were identified using the NIST’11 and Wiley 10 mass spectral libraries. The article first studied and conducted a comparative analysis of lipophilic substances contained in the fruits of the plant Rosa canina L, harvested in the Almaty region. The extracts mainly include hydrocarbons, derivatives of higher carboxylic acids, higher alcohols and some other substances, in particular butyl tetradecyl ether of hydrochloric acid, [4- (2-methylpentanoylsulfamoyl) phenyl] amide of 2-methylpentanoic acid in hexane extract and, butyl undecyl ether sulfuric acid, eicosyl trifluoroacetate and ethoxycarbonyl-3-methyl-4-azafluorenone, 2-fluorenilim in the chloroform extract. Further work will be continued in order to determine the potential biological activity of the obtained extracts. Keywords: Rosa canina L., СКФ-экстракция, никотин, GC-MS, химический состав.

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19

Hsiao, Hsu-Chin, Shue-Ming Kao, and Hung-Shan Weng. "Synthesis ofn-Butyl Phenyl Ether by Tri-Liquid-Phase Catalysis Using Poly(ethylene glycol)-600 as a Catalyst. 1. Analysis of Factors Affecting the Formation of a Third Liquid Phase." Industrial & Engineering Chemistry Research 39, no. 8 (August 2000): 2772–78. http://dx.doi.org/10.1021/ie990824t.

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20

Martin, Gonzalo, Henry Martinez, and Julian Ascanio. "Gas phase thermolysis of benzylt-butyl sulfide, phenylt-butyl sulfide, and phenylt-butyl ether." International Journal of Chemical Kinetics 21, no. 3 (March 1989): 193–206. http://dx.doi.org/10.1002/kin.550210305.

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21

Hsiao, Sheng-Huei, and Liang-Ru Dai. "Synthesis and properties of novel aromatic poly(o-hydroxy amide)s and polybenzoxazoles based on the bis(ether benzoyl chloride)s from hydroquinone and its methyl-,tert-butyl-, and phenyl-substituted derivatives." Journal of Polymer Science Part A: Polymer Chemistry 37, no. 13 (July 1, 1999): 2129–36. http://dx.doi.org/10.1002/(sici)1099-0518(19990701)37:13<2129::aid-pola28>3.0.co;2-o.

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22

Pincock, A. L., and J. A. Pincock. "The structure, photochemical reactivity, and photophysical properties of adamantyl X-substituted aryl ethers and a comparison with the alkyl groups, methyl, tert-butyl, and allyl." Canadian Journal of Chemistry 83, no. 9 (September 1, 2005): 1237–52. http://dx.doi.org/10.1139/v05-117.

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The structure, photophysical properties, and photochemistry of the adamantyl aryl ethers 1 in both methanol and cyclohexane have been examined. UV absorption spectra, 13C NMR chemical shifts, X-ray structures, and Gaussian calculations (B3LYP/6-31G(d)) indicate that these ethers adopt a 90° conformer in the ground state. In contrast, fluorescence spectra, excited singlet state lifetimes, and calculations (TDDFT) indicated a 0° conformer is preferred in the first excited singlet state S1. Irradiation in either solvent results in the formation of adamantane and the corresponding phenol as the major products, both derived from radical intermediates generated by homolytic cleavage of the ether bond. The 4-cyano substituted ether 1j was the only one to form the ion-derived product, 1-methoxyadamantane (16% yield), on irradiation in methanol. Rate constants of bond cleavage for these ethers from S1 were estimated by two different methods by comparison with the unreactive anisoles 2, but the effect of substituents was too small to determine structurereactivity correlations. The temperature dependence of the quantum yields of the fluorescence of the unsub stituted, 4-methoxy and 4-cyano derivatives of 1 and 2 were also determined. These results indicated that the activated process for 1 was mainly bond cleavage for the 4-cyano substrate whereas for 2, it was internal conversion and intersystem crossing. Key words: aryl ether photochemistry, fluorescence, excited-state rate constants, excited-state temperature effects.

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23

Khatri, Praveen K., Manvi Manchanda, Indrajit K. Ghosh, and Suman L. Jain. "Polymer impregnated sulfonated carbon composite solid acid catalyst for alkylation of phenol with methyl-tert-butyl ether." RSC Advances 5, no. 5 (2015): 3286–90. http://dx.doi.org/10.1039/c4ra11033a.

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A polymer impregnated sulfonated carbon composite solid acid catalyst was synthesized via sulfonation of a composite material and used for the alkylation of phenol using methyl-tert-butyl ether as an alkylating agent in a pressure reactor under autogenous pressure.

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24

Gautier, Mathieu, Fabrice Muller, and Lydie Le Forestier. "Interactions of ammonium-smectite with volatile organic compounds from leachates." Clay Minerals 52, no. 1 (March 2017): 143–59. http://dx.doi.org/10.1180/claymin.2017.052.1.10.

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AbstractThe percolation of water through waste landfills produces leachates with high concentrations of which can generate -exchanged clays within geochemical barriers. These leachates also contain several volatile organic compounds (VOCs) which can interact with the clay barrier. The aim of the present study was to characterize the sorption of eight short-chain VOCs (acetonitrile, methyl tert-butyl ether, dichloromethane, benzene, phenol, ethanol, acetone and aniline) on -smectite, and to identify their sorption mechanisms. The samples treated were characterized by carbon and nitrogen elemental analysis, infrared spectroscopy, powder X-ray diffraction, and thermogravimetric analysis. For acetonitrile, methyl tert-butyl ether, dichloromethane and benzene, no sorption was detected. Phenol, ethanol and acetone were sorbed very weakly, through Van der Waals interactions. Aniline molecules were sorbed strongly on -smectite mainly with hydrogen bonds between aniline and interlayer water molecules. However, aniline sorption decreased the hydrophilic character of the -smectite, which may increase the permeability of the clay barrier.

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25

Julia, Marc, Daniel Uguen, Jean-Noël Verpeaux, and Da Zhang. "tert-Butyl Vinyl Ethers fromtert-Butoxymethyl Phenyl Sulfone." Synlett 1991, no. 07 (1991): 505–6. http://dx.doi.org/10.1055/s-1991-20779.

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26

Wang, Lan Sheng, and Wan Xi Peng. "Py-GC-MS Analysis on Biomass Energy Components from Wood Extractives of Eucalyptus urophydis under High Temperature." Applied Mechanics and Materials 164 (April 2012): 30–32. http://dx.doi.org/10.4028/www.scientific.net/amm.164.30.

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In order to widely use Eucalyptus urophydis wood, its ether/acetone extractives were identified by Py-GC/MS. The main and abundant constituents of 750°С pyrolysis products were 1,3-butadiene, 2-methyl-(5.9%), benzofuran, 2,3-dihydro-(4.11%), 1,3-butadiene(3.69%), stigmastan-3,5-diene (3.66%),.gamma.-sitosterol(2.13%), 2-butene, 2,3-dimethyl-(2.03%), toluene (1.92%), 1,4- cyclohexadiene,1-methyl-(1.76%), 1h-indene, 5-butyl-6-hexyloctahydro-(1.73%), 1,3-cyclohexadiene(1.66%), phenol(1.58%), 1-hexene(1.54%), sulfide, bis(2-cyano-3,4- dihydro- 2,3,3-trimethyl-2h-pyrrol-5-yl)- (1.46%), benzene(1.38%), phenol, 4-methyl-(1.35%), cholest-8(14)- ene-3,15-dione(1.23%), acetic acid(1.21%), benzene, 1,2,4-trimethyl-(1.2%), stigmast-4-en-3-one (1.12%), 1-decene(1.1%), 1-heptene(1.08%),etc. So the ether/acetone extractives of Eucalyptus urophydis biomass were used as biomass energy.

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27

Egutkin, N. L., and A. M. Syrkin. "Extraction of phenol from aqueous solutions by methyl tert-butyl ether." Oil and Gas Business, no. 1 (February 2014): 206–19. http://dx.doi.org/10.17122/ogbus-2014-1-206-219.

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28

Santos, A. Mafalda, M. Fernanda N. N. Carvalho, Adelino M. Galvão, and Armando J. L. Pombeiro. "Reactivity Trends in the Reaction of Alkynes with 3-Oxo-camphorsulfonylimine." Zeitschrift für Naturforschung B 57, no. 6 (June 1, 2002): 691–98. http://dx.doi.org/10.1515/znb-2002-0616.

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Abstract The regioselective addition of deprotonated alkynes (phenyl-1-propyne, propargyl ether or tetrahydropyran-protected 3-butyn-1-ol) to the imine group was identified as a competitive process to the nucleophilic addition to the keto group of (1S)-3-oxo-camphorsulfonylimine. The selectivity of the process depends on the characteristics of the nucleophile and the reaction conditions. In the case of propargyl ether it was possible to render the imine addition the main process.The structural characterization of compounds 1, 2, 6 by X-ray diffraction analysis show that the C2 - C3 bond becomes longer upon nucleophilic addition to the imine group of (1S)-3-oxo-camphorsulfonylimine. This trend is believed to favour the ring opening process that undergoes the formation of the spiro type compound 7.

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JULIA, M., D. UGUEN, J. N. VERPEAUX, and D. ZHANG. "ChemInform Abstract: tert-Butyl Vinyl Ethers from tert-Butoxymethyl Phenyl Sulfone." ChemInform 23, no. 10 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199210119.

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Hristova, Krassimira R., Radomir Schmidt, Anu Y. Chakicherla, Tina C. Legler, Janice Wu, Patrick S. Chain, Kate M. Scow, and Staci R. Kane. "Comparative Transcriptome Analysis of Methylibium petroleiphilum PM1 Exposed to the Fuel Oxygenates Methyl tert-Butyl Ether and Ethanol." Applied and Environmental Microbiology 73, no. 22 (September 21, 2007): 7347–57. http://dx.doi.org/10.1128/aem.01604-07.

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ABSTRACT High-density whole-genome cDNA microarrays were used to investigate substrate-dependent gene expression of Methylibium petroleiphilum PM1, one of the best-characterized aerobic methyl tert-butyl ether (MTBE)-degrading bacteria. Differential gene expression profiling was conducted with PM1 grown on MTBE and ethanol as sole carbon sources. Based on microarray high scores and protein similarity analysis, an MTBE regulon located on the megaplasmid was identified for further investigation. Putative functions for enzymes encoded in this regulon are described with relevance to the predicted MTBE degradation pathway. A new unique dioxygenase enzyme system that carries out the hydroxylation of tert-butyl alcohol to 2-methyl-2-hydroxy-1-propanol in M. petroleiphilum PM1 was discovered. Hypotheses regarding the acquisition and evolution of MTBE genes as well as the involvement of IS elements in these complex processes were formulated. The pathways for toluene, phenol, and alkane oxidation via toluene monooxygenase, phenol hydroxylase, and propane monooxygenase, respectively, were upregulated in MTBE-grown cells compared to ethanol-grown cells. Four out of nine putative cyclohexanone monooxygenases were also upregulated in MTBE-grown cells. The expression data allowed prediction of several hitherto-unknown enzymes of the upper MTBE degradation pathway in M. petroleiphilum PM1 and aided our understanding of the regulation of metabolic processes that may occur in response to pollutant mixtures and perturbations in the environment.

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Tristantini, Dewi, Humala Paulus Hakim, and Muhammad Fadly Zuliardy. "Addition of egbe and ethanol to enhance mes performance as chemical flooding material." Jurnal Teknik Kimia Indonesia 10, no. 3 (October 2, 2018): 120. http://dx.doi.org/10.5614/jtki.2011.10.3.2.

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Methyl ester sulfonate (MES) performance as chemical flooding material for EOR was investigated by adding emulsifier ethyl glycol mono butyl ether (EGBE) and ethanol. MES had interfacial tension (IFT) value as low as 10-3 dyne/cm, but its disadvantage was low solubility in brine water. Repairing this nature, MES was modified by adding nonyl phenol ethoxylate (Tergitol, as secondary surfactant), EGBE and ethanol. The mixed surfactant was tested for IFT value, solubility, and thermal influence to IFT value in various concentrations. The result indicated a significant effect of emulsifier concentration to IFT value. The longer carbon chains, the easier micelle interaction was formed. The positive effects to solubility were caused by the polarity of long chain EGBE and the increase of micro emulsion stability by ethanol. The best formulas were 1% concentration surfactant in brine water consist of MES 40%, Tergitol 20%, ethanol 40% and 0.3% of MES 40%, Tergitol 20%, EGBE 40%. These formulas also had better solubility than MES alone, since they only form one phase. Heat treatment at 62.5 oC for 1 day caused lower IFT because of increasing interaction between emulsifier and micelle. Further heating resulted in a higher IFT as the emulsifier structure collapsed, which made interactions difficult to achieve. Keywords: EOR, interfacial tension, methyl ester sulfonate, non-ionic, surfactantAbstrakKinerja metil ester sulfonat (MES) sebagai bahan chemical flooding untuk EOR telah dilakukan dengan menambahkan pengemulsi etil glikol mono butil eter (EGBE) dan etanol. MES memiliki nilai tegangan permukaan (IFT) sebesar 10-3 dyne/cm, tetapi memiliki kelarutan yang rendah dalam air formasi. Untuk memperbaiki sifat ini, MES ditambahkan dengannonyl phenol ethoxylate (Tergitol) sebagai surfaktan kedua, EGBE dan etanol. Hasil formulasi surfaktan diuji nilai IFT, kelarutan dan pengaruh termal terhadap nilai IFT dalam berbagai tingkat konsentrasi. Hasil pengujian mengindikasikan adanya pengaruh konsentrasi pengemulsi yang besar terhadap nilai IFT. Rantai karbon yang lebih panjang berakibat semakin mudah interaksi micelle terjadi. Kelarutan yang semakin tinggi disebabkan polaritas dari rantai panjang EGBE dan meningkatnya stabilitas mikroemulsi oleh alkohol. Hasil formulasi terbaik didapatkan pada konsentrasi surfaktan 1% dengan MES 40%, Tergitol 20%, Alkohol 40% dan konsentrasi surfaktan 0,3% dengan MES 40%, Tergitol 20%, EGBE 40%. Formula ini memiliki kelarutan yang lebih baik daripada MES karena hanya membentuk 1 fase. Pengaruh pemanasan 62,5 oC selama 1 hari menyebabkan IFT semakin rendah karena meningkatnya interaksi antara pengemulsi dan micelle. Pemanasan yang berlebihan menyebabkan IFT naik karena rusaknya struktur pengemulsi sehingga interaksi sulit terjadi.Kata kunci: EOR, metil ester sulfonat, non-ionik, surfaktan, tegangan permukaan

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Lund, Vidar, Mary Anderson-Glenna, Ingun Skjevrak, and Inger-Lise Steffensen. "Long-term study of migration of volatile organic compounds from cross-linked polyethylene (PEX) pipes and effects on drinking water quality." Journal of Water and Health 9, no. 3 (May 10, 2011): 483–97. http://dx.doi.org/10.2166/wh.2011.165.

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The objectives of this study were to investigate migration of volatile organic compounds (VOCs) from cross-linked polyethylene (PEX) pipes used for drinking water produced by different production methods, and to evaluate their potential risk for human health and/or influence on aesthetic drinking water quality. The migration tests were carried out in accordance with EN-1420-1, and VOCs were analysed by gas chromatography-mass spectrometry. The levels of VOC migrating from new PEX pipes were generally low, and decreasing with time of pipe use. No association was found between production method of PEX pipes and concentration of migration products. 2,4-di-tert-butyl phenol and methyl tert-butyl ether (MTBE) were two of the major individual components detected. In three new PEX pipes, MTBE was detected in concentrations above the recommended US EPA taste and odour value for drinking water, but decreased below this value after 5 months in service. However, the threshold odour number (TON) values for two pipes were similar to new pipes even after 1 year in use. For seven chemicals for which conclusions on potential health risk could be drawn, this was considered of no or very low concern. However, odour from some of these pipes could negatively affect drinking water for up to 1 year.

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Hu, Shi-kai, Si Chen, Xiu-ying Zhao, Ming-ming Guo, and Li-qun Zhang. "The Shape-Memory Effect of Hindered Phenol (AO-80)/Acrylic Rubber (ACM) Composites with Tunable Transition Temperature." Materials 11, no. 12 (December 4, 2018): 2461. http://dx.doi.org/10.3390/ma11122461.

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To broaden the types and scope of use of shape-memory polymers (SMPs), we added the hindered phenol 3,9-bis[1,1-dimethyl-2-{b-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro-[5,5]-undecane (AO-80), which comprises small organic molecules, to acrylic rubber (ACM) to form a series of AO-80/ACM rubber composites. The structural, thermal, mechanical property, and shape-memory properties of the AO-80/ACM rubber composites were investigated. We identified the formation of intra-molecular hydrogen bonding between –OH of AO-80 and the carbonyl groups and the ether groups of ACM molecules. The amount of AO-80 used can be adjusted to tailor the transition temperature. AO-80/ACM rubber composites showed excellent shape recovery and fixity. The approach for adjusting the transition temperature of AO-80/ACM rubber composites provides remarkable ideas for the design and preparation of new SMPs.

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Hartung, Jens. "Stereoselective syntheses of functionalized cyclic ethers via (Schiff-base)vanadium(V)-catalyzed oxidations." Pure and Applied Chemistry 77, no. 9 (January 1, 2005): 1559–74. http://dx.doi.org/10.1351/pac200577091559.

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(Schiff-base)vanadium(V) complexes catalyze the oxidation of Br- (formation of Br2) and the stereoselective synthesis of functionalized tetrahydrofurans from substituted bishomoallylic alcohols. In both instances, tert-butyl hydroperoxide (TBHP) serves as primary oxidant. The oxidation of Br- was applied as the key step for stereo- and 6-endo-selectively constructing the 2,2,3,5,6,6-substituted tetrahydropyran nucleus of the marine natural product aplysiapyranoid A starting from an adequately substituted bishomoallylic alcohol. In the absence of Br-, 1-alkyl-, 1-vinyl-, and 1-phenyl-5,5-dimethyl-substituted bishomoallylic alcohols are selectively oxygenated to furnish 2,5-cis-configured tetrahydrofurans as major products. 2- Or 3-substituted ω,ω-dimethyl-substituted bishomoallylic alcohols afford trans-disubstituted tetrahydrofurans under these conditions. Oxidation of substituted 4-penten-1-ols, i.e., substrates with a terminal π-bond, proceeds with a preference for formation of trans-disubstituted tetrahydrofurans. According to data from (i) 51V NMR spectroscopy, (ii) mass spectrometry, (iii) a structure-selectivity survey, (iv) competition kinetics, and (v) a stereochemical analysis, the oxygen atom transfer onto a bishomoallylic alcohol occurs in a peroxide- and alkenol-loaded (Schiff-base)vanadium(V) complex.

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Chandra, K. Gokul, and M. M. Sharma. "Alkylation of phenol with MTBE and other tert-butyl ethers: cation exchange resins as catalysts." Catalysis Letters 19, no. 4 (1993): 309–17. http://dx.doi.org/10.1007/bf00767072.

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Gómez, Edison Díaz, and Helmut Duddeck. "Origin of13C complexation shifts in the adduct formation of 2-butyl phenyl ethers with a dirhodium tetracarboxylate complex." Magnetic Resonance in Chemistry 46, no. 1 (December 20, 2007): 23–29. http://dx.doi.org/10.1002/mrc.2116.

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37

Yadav, Ganapati D., and Nirav S. Doshi. "Alkylation of phenol with methyl-tert-butyl ether and tert-butanol over solid acids: efficacies of clay-based catalysts." Applied Catalysis A: General 236, no. 1-2 (September 2002): 129–47. http://dx.doi.org/10.1016/s0926-860x(02)00300-9.

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38

Hariharan, Vidhya, Jared Klarquist, Mary J. Reust, Amy Koshoffer, Mark D. McKee, Raymond E. Boissy, and I. Caroline Le Poole. "Monobenzyl Ether of Hydroquinone and 4-Tertiary Butyl Phenol Activate Markedly Different Physiological Responses in Melanocytes: Relevance to Skin Depigmentation." Journal of Investigative Dermatology 130, no. 1 (January 2010): 211–20. http://dx.doi.org/10.1038/jid.2009.214.

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39

Shaabani, Ahmad, Ali Hossein Rezayan, Marjan Heidary, and Afshin Sarvary. "A mild and efficient approach for the selective deprotection of benzyl and phenyl trimethylsilyl ethers in 1-butyl-3-methyl-imidazolium chloride." Monatshefte für Chemie - Chemical Monthly 139, no. 12 (July 9, 2008): 1471–74. http://dx.doi.org/10.1007/s00706-008-0960-y.

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40

Shen, Chensi, Shaoshuai Wu, Hui Chen, Sadia Rashid, and Yuezhong Wen. "Phthalate degradation by glow discharge plasma enhanced with pyrite in aqueous solution." Water Science and Technology 74, no. 6 (June 27, 2016): 1365–75. http://dx.doi.org/10.2166/wst.2016.316.

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In order to prevent health risk from potential exposures to phthalates, a glow discharge plasma (GDP) process was applied for phthalate degradation in aqueous solution. The results revealed that the phthalate derivatives 4-hydroxyphthalic acid, 4-methylphthalic acid and 4-tert-butylphthalic anhydride could be degraded efficiently in GDP process (498 V, 0.2 A) with high removal efficiencies of over 99% in 60 minutes. Additionally, pyrite as a promising heterogeneous iron source in the Fenton reaction was found to be favorable for GDP process. The phthalate degradation reaction could be significantly enhanced by the continuous formation of •OH and the inhibition of the quenching reaction in the pyrite Fenton system due to the constant dissolution of Fe(II) from pyrite surface. Meanwhile, the initial pH value showed little impact on the degradation of phthalates and the energy efficiency of GDP system for phthalate degradation ranged between 0.280 × 10−9 and 1.210 × 10−9 mol/J, which is similar to the GDP system with phenol, bisphenol A and methyl tert-butyl ether as the substrates. Further, the X-ray diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy analyses indicated that the pyrite was relatively stable in GDP system and there was no obvious polymeric compound formed on the catalyst surface. Overall, this GDP process offers high removal efficiency, simple technology, considerable energy efficiency and the applicability to salt-containing phthalate wastewater.

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Alauddin, M., and Ronald E. Verrall. "Apparent molal volume and solubility studies of 2,6-di-tert-buty-4-methylphenol, 2-tert-butyl-4-methoxyphenol, and 2,6-di-tert-butyl-4-(hydroxymethyl)phenol in aqueous micelle solutions of poly(oxyethylene) (23) lauryl ether as a function of micelle concentration and temperature." Journal of Physical Chemistry 91, no. 7 (March 1987): 1802–9. http://dx.doi.org/10.1021/j100291a025.

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42

Ma, Xian-kui, Xiao-fei Li, Jian-yong Zhang, Jie Lei, Wei-wei Li, and Gang Wang. "Analysis of the Volatile Components in Selaginella doederleinii by Headspace Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry." Molecules 25, no. 1 (December 27, 2019): 115. http://dx.doi.org/10.3390/molecules25010115.

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Selaginella doederleinii (SD) is a perennial medicinal herb widely distributed in China. In this study, the volatile components of SD from two regions (24 batches), namely Zhejiang and Guizhou, were determined by combining headspace solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME/GC-MS). After investigating different influence factors, the optimal conditions for extraction were as follows: The sample amount of 1 g, the polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber of 65 µm, the extraction time of 20 min, and the extraction temperature of 100 °C. Based on the above optimum conditions, 58 volatiles compounds, including 20 terpenes, 11 alkanes, 3 alcohols, 6 ketones, 3 esters, 11 aldehydes, 1 ether, 1 aromatic, 1 phenol, and 1 furan, were found and identified in SD. Furthermore, hierarchical cluster analysis and principal component analysis were successfully applied to distinguish the chemical constituents of SD from two regions. Additionally, anethol, zingerone, 2,4-di-tert-butylphenol, ledene, hexyl hexanoate, α-cadinol, phytone, hinesol, decanal, octadecene, cedren, 7-tetradecene, copaene, β-humulene, 2-butyl-2-octenal, tetradecane, cedrol, calacorene, 6-dodecanone, β-caryophyllene, 4-oxoisophorone, γ-nonanolactone, 2-pentylfuran, 1,2-epoxyhexadecane, carvacrol, n-pentadecane, diisobutyl phthalate, farnesene, n-heptadecane, linalool, 1-octen-3-ol, phytane, and β-asarone were selected as the potential markers for discriminating SD from 24 habitats in Zhejiang and Guizhou by partial least squares discrimination analysis (PLS-DA). This study revealed the differences in the components of SD from different regions, which could provide a reference for the future quality evaluation.

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Edgell, Kenneth W., Elizabeth J. Erb, Raymond J. Wesselman, James E. Longbottom, N. Dodhiwala, M. Fencl, R. Hanisch, et al. "Gas Chromatographic/Electron Capture Detection Method for Determination of Chlorinated Acids in Water: Collaborative Study." Journal of AOAC INTERNATIONAL 76, no. 5 (September 1, 1993): 1098–112. http://dx.doi.org/10.1093/jaoac/76.5.1098.

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Abstract A U.S. Environmental Protection Agency (USEPA) inter laboratory method validation study was conducted on USEPA Method 515.1, "Determination of Chlorinated Acids in Water by Gas Chromatography with an Electron Capture Detector. "This method is one of the 6 pesticide methods developed for the USEPA National Pesticide Survey (NPS). Method recovery and precision for analyses of sub-ppb to low-ppb concentrations of chlorinated acids were determined in reagent water and finished drinking waters. The analytes evaluated in the study included the 12 pesticides that were quantitatively measured in the National Pesticide Survey (bentazon, 2,4-D, 2,4-DB, 3,5-dichlorobenzoic acid, DCPA-diacid, dicamba, dichlorprop, 5-hydroxydicamba, pentachlorophenol, picloram, 2,4,5- T, and 2,4,5-TP) and 5 pesticides (acif luorfen, chloramben, dalapon, dinoseb, and 4-n it ro phenol) that were only qualitatively assessed in the National Pesticide Survey because of recognized method imprecision. The study design was based on Youden's nonreplicate plan for collaborative tests of analytical methods. The waters were spiked with 17 chlorinated acids, each at 6 concentration levels, prepared as 3 Youden pairs. Eight laboratories extracted the spiked test waters at pH <2 with ethyl ether, performed a solvent exchange with methyl tert-butyl ether, prepared methyl esters of the extracted acids using diazomethane, and analyzed an aliquot of each derivatized extract by gas chromatography with electron capture detection. The submitted data were analyzed using a USEPA computer program, which measured recovery and precision for each of the 17 compounds and compared the performance of the method between water types. Method 515.1 was judged acceptable for the 12 NPS analytes recovered quantitatively; mean percent recoveries at 10-15 times the method detection limits ranged from 79 to 105% in reagent water and from 75 to 123% in finished drinking water. In reagent water, overall precision (reproducibility relative standard deviation, RSDR) ranged from 9.6 to 34.2% and in finished drinking water, the RSDR ranged from 11.9 to 37.0%. Single-analyst precision (RSD for repeatability, RSDr) ranged from 5.8 to 17.7% in reagent water and from 4.6 to 27.9% in drinking water. Results for the 5 other NPS analytes were too inaccurate or imprecise and, for these compounds, supported use of the method for qualitative measurements only; the 5 compounds are not included in the adopted method. The method has been adopted first action by AOAC INTERNATIONAL for determination of residues of 12 chlorinated acids in finished drinking water.

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MARTIN, G., H. MARTINEZ, and J. ASCANIO. "ChemInform Abstract: Gas Phase Thermolysis of Benzyl tert.-Butyl Sulfide, Phenyl tert.-Butyl Sulfide, and Phenyl tert.-Butyl Ether." ChemInform 20, no. 22 (May 30, 1989). http://dx.doi.org/10.1002/chin.198922085.

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Dakternieks, D., K. Jurkschat, R. Tozer, and E. R. T. Tiekink. "Crystal structure of di(2-methoxy-3-t-butyl-5-methyl phenyl)methyl methyl ether, (H3COCH3C4H9C6H2)2HCOCH3." Zeitschrift für Kristallographie - Crystalline Materials 209, no. 8 (January 1, 1994). http://dx.doi.org/10.1524/zkri.1994.209.8.693.

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Higuchi, Yudai, Shogo Aoki, Hiroki Takenami, Naofumi Kamimura, Kenji Takahashi, Shojiro Hishiyama, Christopher S. Lancefield, et al. "Bacterial Catabolism of β-Hydroxypropiovanillone and β-Hydroxypropiosyringone Produced in the Reductive Cleavage of Arylglycerol-β-Aryl Ether in Lignin." Applied and Environmental Microbiology 84, no. 7 (January 26, 2018). http://dx.doi.org/10.1128/aem.02670-17.

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ABSTRACTSphingobiumsp. strain SYK-6 converts four stereoisomers of arylglycerol-β-guaiacyl ether into achiral β-hydroxypropiovanillone (HPV) via three stereospecific reaction steps. Here, we determined the HPV catabolic pathway and characterized the HPV catabolic genes involved in the first two steps of the pathway. In SYK-6 cells, HPV was oxidized to vanilloyl acetic acid (VAA) via vanilloyl acetaldehyde (VAL). The resulting VAA was further converted into vanillate through the activation of VAA by coenzyme A. A syringyl-type HPV analog, β-hydroxypropiosyringone (HPS), was also catabolized via the same pathway. SLG_12830 (hpvZ), which belongs to the glucose-methanol-choline oxidoreductase family, was isolated as the HPV-converting enzyme gene. AnhpvZmutant completely lost the ability to convert HPV and HPS, indicating thathpvZis essential for the conversion of both the substrates. HpvZ produced inEscherichia colioxidized both HPV and HPS and other 3-phenyl-1-propanol derivatives. HpvZ localized to both the cytoplasm and membrane of SYK-6 and used ubiquinone derivatives as electron acceptors. Thirteen gene products of the 23 aldehyde dehydrogenase (ALDH) genes in SYK-6 were able to oxidize VAL into VAA. Mutant analyses suggested that multiple ALDH genes, including SLG_20400, contribute to the conversion of VAL. We examined whether the genes encoding feruloyl-CoA synthetase (ferA) and feruloyl-CoA hydratase/lyase (ferBandferB2) are involved in the conversion of VAA. Only FerA exhibited activity toward VAA; however, disruption offerAdid not affect VAA conversion. These results indicate that another enzyme system is involved in VAA conversion.IMPORTANCECleavage of the β-aryl ether linkage is the most essential process in lignin biodegradation. Although the bacterial β-aryl ether cleavage pathway and catabolic genes have been well documented, there have been no reports regarding the catabolism of HPV or HPS, the products of cleavage of β-aryl ether compounds. HPV and HPS have also been found to be obtained from lignin by chemoselective catalytic oxidation by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone/tert-butyl nitrite/O2, followed by cleavage of the β-aryl ether with zinc. Therefore, value-added chemicals are expected to be produced from these compounds. In this study, we determined the SYK-6 catabolic pathways for HPV and HPS and identified the catabolic genes involved in the first two steps of the pathways. Since SYK-6 catabolizes HPV through 2-pyrone-4,6-dicarboxylate, which is a building block for functional polymers, characterization of HPV catabolism is important not only for understanding the bacterial lignin catabolic system but also for lignin utilization.

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WALKER, J. A., and W. TSANG. "ChemInform Abstract: Single-Pulse Shock Tube Studies on the Thermal Decomposition of n-Butyl Phenyl Ether, n-Pentylbenzene, and Phenotole and the Heat of Formation of Phenoxy and Benzyl Radicals." ChemInform 21, no. 33 (August 14, 1990). http://dx.doi.org/10.1002/chin.199033078.

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Dobele, Galina, Tatiana Dizhbite, Jevgenija Ponomarenko, Igor Urbanovich, Jana Kreicberga, and Valdis Kampars. "Isolation and characterization of the phenolic fractions of wood pyrolytic oil." Holzforschung 65, no. 4 (June 1, 2011). http://dx.doi.org/10.1515/hf.2011.049.

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Abstract A fraction of pyrolytic oils (PyO) – obtained by fast pyrolysis of alder (Alnus incana), ash-tree (Fraxinus excelsior) and aspen (Populus tremula) in a laboratory scale reactor – was precipitated in water. This hydrophobic moiety of PyO is called pyrolytic lignin (PyL). The composition of the volatile monomeric compounds of PyO and the PyL fraction was determined by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). It has been found that PyL has a high content of phenolic products (between 75% and 83%), which varies depending on the wood species. The antioxidant properties of the PyL fraction were studied and it was demonstrated that the antioxidant activity determined in different tests exceeded the corresponding activity of alkali lignin. The antioxidant properties of PyL are on the same level as those of the widely used antioxidants, such as rutin, trolox, curcumine, and tert-butylhydroquinone (TBHQ). A new method was developed for the extraction of a monomeric phenol fraction (Py-monPh) from PyO by means of the organic solvent methyl tert-butyl ether (MTBE). The Py-monPh can be considered as a promising source of antioxidants.

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Shaabani, Ahmad, Ali Hossein Rezayan, Marjan Heidary, and Afshin Sarvary. "ChemInform Abstract: A Mild and Efficient Approach for the Selective Deprotection of Benzyl and Phenyl Trimethylsilyl Ethers in 1-Butyl-3-methylimidazolium Chloride." ChemInform 40, no. 12 (March 24, 2009). http://dx.doi.org/10.1002/chin.200912044.

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ALAUDDIN, M., and R. E. VERRALL. "ChemInform Abstract: Apparent Molal Volume and Solubility Studies of 2,6-Di-tert-butyl-4-methylphenol, 2-tert-Butyl-4-methoxyphenol, and 2,6-Di-tert-butyl-4-(hydroxymethyl)phenol in Aqueous Micelle Solutions of Poly(oxyethylene) (23) Lauryl Ether as a Fun." ChemInform 18, no. 31 (August 4, 1987). http://dx.doi.org/10.1002/chin.198731055.

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Journal articles on the topic 'Butyl phenyl ether'

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