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Zhao M, Chen M, Wang T, Yang S, Peng Q, Tang P. Fluorocarbonylation via palladium/phosphine synergistic catalysis. Nat Commun 2023; 14:4583. [PMID: 37524725 PMCID: PMC10390470 DOI: 10.1038/s41467-023-40180-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 07/13/2023] [Indexed: 08/02/2023] Open
Abstract
Despite the growing importance of fluorinated organic compounds in pharmaceuticals, agrochemicals, and materials science, the introduction of fluorine into organic molecules is still a challenge, and no catalytic fluorocarbonylation of aryl/alkyl boron compounds has been reported to date. Herein, we present the development of palladium and phosphine synergistic redox catalysis of fluorocarbonylation of potassium aryl/alkyl trifluoroborate. Trifluoromethyl arylsulfonate (TFMS), which was used as a trifluoromethoxylation reagent, an easily handled and bench-scale reagent, has been employed as an efficient source of COF2. The reaction operates under mild conditions with good to excellent yields and tolerates diverse complex scaffolds, which allows efficient late-stage fluorocarbonylation of marked small-molecule drugs. Mechanistically, the key intermediates of labile Brettphos-Pd(II)-OCF3 complex and difluoro-Brettphos were synthesized and spectroscopically characterized, including X-ray crystallography. A detailed reaction mechanism involving the synergistic redox catalytic cycles Pd(II)/(0) and P(III)/(V) was proposed, and multifunction of phosphine ligand was identified based on 19F NMR, isotope tracing, synthetic, and computational studies.
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Affiliation(s)
- Mingxin Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Miao Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Tian Wang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Shuhan Yang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China
| | - Qian Peng
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China.
- Haihe Laboratory of Sustainable Chemical Transformations, 300192, Tianjin, China.
| | - Pingping Tang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, 300071, Tianjin, China.
- Haihe Laboratory of Sustainable Chemical Transformations, 300192, Tianjin, China.
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Hyttinen N, Otkjær RV, Iyer S, Kjaergaard HG, Rissanen MP, Wennberg PO, Kurtén T. Computational Comparison of Different Reagent Ions in the Chemical Ionization of Oxidized Multifunctional Compounds. J Phys Chem A 2017; 122:269-279. [PMID: 29200296 DOI: 10.1021/acs.jpca.7b10015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
High pressure anion chemical ionization is commonly used for the detection of neutral molecules in the gas phase. The detection efficiency in these measurements depends on how strongly the reagent ion binds to the neutral target molecule. We have calculated the binding strength of nitrate (NO3-), acetate (CH3C(O)O-), lactate (CH3CH(OH)C(O)O-), trifluoroacetate (CF3C(O)O-), trifluoromethanolate (CF3O-), bromide (Br-), and iodide (I-) reagent ions to ten different products derived from the OH radical-initiated oxidation of butadiene. We found that the binding of these oxidation products to the reagent ions depends almost linearly on the number of oxygen atoms in the target molecule, with the precise chemical identity of the compound (e.g., the number and relative position of hydroxyl or hydroperoxy groups) playing a more minor role. For acetate, the formation free energy decreases on average by around 4 kcal/mol when the number of oxygen atoms in the sample molecule increases by one. For the other reagent ions the corresponding decrease is around 3 kcal/mol. For all of the molecules studied, acetate forms the most stable clusters and I- the least stable. We also investigated the effect of humidity on the chemical ionization by calculating how strongly water molecules bind to both the reagent ions and the ion-molecule clusters. Water binds much more strongly to the reagent ion monomers compared to the reagent ion "dimers" (defined here as a cluster of the reagent anion with the corresponding neutral conjugate acid, e.g., HNO3(NO3-)) or the ion-molecule clusters. This likely leads to a stronger humidity dependence when using reagent ions that are not able to form reagent ion dimers (such as CF3C(O)O-, CF3O-, Br-, and I-).
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Affiliation(s)
- Noora Hyttinen
- Department of Chemistry, University of Helsinki , P.O. Box 55, FI-00014 Helsinki, Finland
| | - Rasmus V Otkjær
- Department of Chemistry, DK-2100, Copenhagen Ø, University of Copenhagen , Copenhagen, Denmark
| | - Siddharth Iyer
- Department of Chemistry, University of Helsinki , P.O. Box 55, FI-00014 Helsinki, Finland
| | - Henrik G Kjaergaard
- Department of Chemistry, DK-2100, Copenhagen Ø, University of Copenhagen , Copenhagen, Denmark
| | - Matti P Rissanen
- Department of Physics, University of Helsinki , P.O. Box 64, FI-00014 Helsinki, Finland
| | - Paul O Wennberg
- Division of Engineering and Applied Science and Division of Geological and Planetary Sciences, California Institute of Technology , 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Theo Kurtén
- Department of Chemistry, University of Helsinki , P.O. Box 55, FI-00014 Helsinki, Finland
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Inomata S, Hirokawa J. Non-radioactive Chemical Ionization Mass Spectrometry Using Acetic Acid–Acetate Cluster as a Reagent Ion for the Real-time Measurement of Acids and Hydroperoxides. CHEM LETT 2017. [DOI: 10.1246/cl.160828] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Satoshi Inomata
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506
| | - Jun Hirokawa
- Hokkaido University, Kita 10 Nishi 5, Sapporo, Hokkaido 060-0810
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Kim S, Guenther A, Apel E. Quantitative and qualitative sensing techniques for biogenic volatile organic compounds and their oxidation products. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2013; 15:1301-1314. [PMID: 23748571 DOI: 10.1039/c3em00040k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The physiological production mechanisms of some of the organics in plants, commonly known as biogenic volatile organic compounds (BVOCs), have been known for more than a century. Some BVOCs are emitted to the atmosphere and play a significant role in tropospheric photochemistry especially in ozone and secondary organic aerosol (SOA) productions as a result of interplays between BVOCs and atmospheric radicals such as hydroxyl radical (OH), ozone (O3) and NOX (NO + NO2). These findings have been drawn from comprehensive analysis of numerous field and laboratory studies that have characterized the ambient distribution of BVOCs and their oxidation products, and reaction kinetics between BVOCs and atmospheric oxidants. These investigations are limited by the capacity for identifying and quantifying these compounds. This review highlights the major analytical techniques that have been used to observe BVOCs and their oxidation products such as gas chromatography, mass spectrometry with hard and soft ionization methods, and optical techniques from laser induced fluorescence (LIF) to remote sensing. In addition, we discuss how new analytical techniques can advance our understanding of BVOC photochemical processes. The principles, advantages, and drawbacks of the analytical techniques are discussed along with specific examples of how the techniques were applied in field and laboratory measurements. Since a number of thorough review papers for each specific analytical technique are available, readers are referred to these publications rather than providing thorough descriptions of each technique. Therefore, the aim of this review is for readers to grasp the advantages and disadvantages of various sensing techniques for BVOCs and their oxidation products and to provide guidance for choosing the optimal technique for a specific research task.
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Affiliation(s)
- Saewung Kim
- Department of Earth System Science, School of Physical Sciences, University of California, Irvine, Irvine, CA 92697, USA.
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Yee LD, Craven JS, Loza CL, Schilling KA, Ng NL, Canagaratna MR, Ziemann PJ, Flagan RC, Seinfeld JH. Secondary organic aerosol formation from low-NO(x) photooxidation of dodecane: evolution of multigeneration gas-phase chemistry and aerosol composition. J Phys Chem A 2012; 116:6211-30. [PMID: 22424261 DOI: 10.1021/jp211531h] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The extended photooxidation of and secondary organic aerosol (SOA) formation from dodecane (C(12)H(26)) under low-NO(x) conditions, such that RO(2) + HO(2) chemistry dominates the fate of the peroxy radicals, is studied in the Caltech Environmental Chamber based on simultaneous gas and particle-phase measurements. A mechanism simulation indicates that greater than 67% of the initial carbon ends up as fourth and higher generation products after 10 h of reaction, and simulated trends for seven species are supported by gas-phase measurements. A characteristic set of hydroperoxide gas-phase products are formed under these low-NO(x) conditions. Production of semivolatile hydroperoxide species within three generations of chemistry is consistent with observed initial aerosol growth. Continued gas-phase oxidation of these semivolatile species produces multifunctional low volatility compounds. This study elucidates the complex evolution of the gas-phase photooxidation chemistry and subsequent SOA formation through a novel approach comparing molecular level information from a chemical ionization mass spectrometer (CIMS) and high m/z ion fragments from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Combination of these techniques reveals that particle-phase chemistry leading to peroxyhemiacetal formation is the likely mechanism by which these species are incorporated in the particle phase. The current findings are relevant toward understanding atmospheric SOA formation and aging from the "unresolved complex mixture," comprising, in part, long-chain alkanes.
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Affiliation(s)
- Lindsay D Yee
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125, United States
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Castellino V, Cheng YL, Acosta E. The hydrophobicity of silicone-based oils and surfactants and their use in reactive microemulsions. J Colloid Interface Sci 2010; 353:196-205. [PMID: 20926096 DOI: 10.1016/j.jcis.2010.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 09/03/2010] [Accepted: 09/04/2010] [Indexed: 11/18/2022]
Abstract
In this work, for the first time, the Hydrophilic-Lipophilic Difference (HLD) framework for microemulsion formulation has been applied to silicone oils and silicone alkyl polyether surfactants. Based on the HLD equations and recently introduced mixing rules, we have quantified the hydrophobicity of the oils according to the equivalent alkane carbon number (EACN). We have found that, in a reference system containing sodium dihexyl sulfosuccinate (SDHS) as the surfactant, 0.65 centistoke (cSt) and 3.0 cSt silicone oils behave like n-dodecane and n-pentadecane, respectively. Silicone alkyl polyether surfactants were found to have characteristic curvatures ranging 3.4-18.9, exceeding that of most non-ionic surfactants. The introduction of methacrylic acid (MAA) and hydroxyethyl methacrylate (HEMA) to the aqueous phase caused a significant negative shift in HLD, indicative of an aqueous phase that is less hydrophilic than pure water. The more hydrophobic surfactants (largest positive curvatures) were used in order to compensate for this effect. These findings have led to the formulation of bicontinuous microemulsions (μEs) containing silicone oil, silicone alkyl polyether and reactive monomers in aqueous solution. Ternary phase diagrams of these systems revealed the potential for silicone-containing polymer composites with bicontinuous morphologies. These findings have also helped to explain the phase behavior of formulations previously reported in literature, and could help in providing a systematic, consistent approach to future silicone oil based microemulsion formulation.
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Affiliation(s)
- Victor Castellino
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St., Toronto, Canada M5S 3E5
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St Clair JM, McCabe DC, Crounse JD, Steiner U, Wennberg PO. Chemical ionization tandem mass spectrometer for the in situ measurement of methyl hydrogen peroxide. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:094102. [PMID: 20886995 DOI: 10.1063/1.3480552] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A new approach for measuring gas-phase methyl hydrogen peroxide [(MHP) CH(3)OOH] utilizing chemical ionization mass spectrometry is presented. Tandem mass spectrometry is used to avoid mass interferences that hindered previous attempts to measure atmospheric CH(3)OOH with CF(3)O(-) clustering chemistry. CH(3)OOH has been successfully measured in situ using this technique during both airborne and ground-based campaigns. The accuracy and precision for the MHP measurement are a function of water vapor mixing ratio. Typical precision at 500 pptv MHP and 100 ppmv H(2)O is ±80 pptv (2 sigma) for a 1 s integration period. The accuracy at 100 ppmv H(2)O is estimated to be better than ±40%. Chemical ionization tandem mass spectrometry shows considerable promise for the determination of in situ atmospheric trace gas mixing ratios where isobaric compounds or mass interferences impede accurate measurements.
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Affiliation(s)
- Jason M St Clair
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA
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Mehta SK, Kaur G, Bhasin KK. Analysis of Tween based microemulsion in the presence of TB drug rifampicin. Colloids Surf B Biointerfaces 2007; 60:95-104. [PMID: 17646089 DOI: 10.1016/j.colsurfb.2007.06.012] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 05/28/2007] [Accepted: 06/03/2007] [Indexed: 11/23/2022]
Abstract
The purpose of present study was to formulate microemulsion composed of oleic acid+phosphate buffer (PB)+Tween 80+ethanol and to investigate its potential as drug delivery system for an antitubercular drug rifampicin. The pseudo-ternary phase diagram has been delineated at constant surfactant/cosurfactant ratio (K(m) 0.55). Conductivity (sigma) and viscosity (keta) studies with variation in Phi (weight fraction of aqueous phase) and omega (molar concentration ratio) show the occurrence of structural changes from water-in-oil (w/o) microemulsion to oil-in-water (o/w). Along with the solubility and partition studies of rifampicin in microemulsion components, the changes in the microstructure of the microemulsion after incorporation of drug have been evaluated using pH, sigma and keta studies. The results have shown that the microemulsion remained stable after the incorporation of rifampicin (in terms of optical texture and phase separation). In addition, the particle size analysis indicates that the microemulsion changes into o/w emulsion at infinite dilution. Dissolution studies infer that a controlled release of rifampicin is expected from o/w emulsion droplet.
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Affiliation(s)
- S K Mehta
- Department of Chemistry and Center of Advanced Studies in Chemistry, Panjab University, Chandigarh 160014, India.
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Mehta SK, Kaur G, Bhasin KK. Incorporation of Antitubercular Drug Isoniazid in Pharmaceutically Accepted Microemulsion: Effect on Microstructure and Physical Parameters. Pharm Res 2007; 25:227-36. [PMID: 17577642 DOI: 10.1007/s11095-007-9355-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2007] [Accepted: 05/18/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE The purpose of present study is to formulate microemulsion composed of oleic acid, phosphate buffer, Tween 80, ethanol and to investigate its potential as drug delivery system for an antitubercular drug isoniazid. MATERIALS AND METHODS The pseudo-ternary phase diagram (Gibbs Triangle) was delineated at constant surfactant/co-surfactant ratio (Km 0.55). Changes in the microstructure were established using conductivity (sigma), viscosity (eta), surface tension (gamma) and density measurements. Dissolution studies and particle size analysis were carried out to understand the release of isoniazid from the microemulsion formulation. Further, partitioning studies and spectroscopic analysis (FT-IR and (1)H NMR) was performed to evaluate the location of drug in the colloidal formulation. RESULTS Physico-chemical analysis of microemulsion system showed the occurrence of structural changes from water-in-oil to oil-in-water microemulsion. It has been observed that the microemulsion remained stable after the incorporation of isoniazid (in terms of optical texture, pH and phase separation). The changes in the microstructure of the microemulsion after incorporation of drug was analyzed on the basis of partition studies of isoniazid in microemulsion components and various parameters viz pH, sigma, eta,gamma. In addition, the particle size analysis indicates that the microemulsion changes into o/w emulsion at infinite dilution. The spectroscopic studies revealed that most of the drug molecules are present in the continuum region of an o/w microemulsion. Dissolution studies infer that a controlled release of drug is expected from o/w emulsion droplet. In the present system the release of isoniazid from microemulsion was found to be non-Fickian. CONCLUSION The present Tween based microemulsion appears beneficial for the delivery of the isoniazid in terms of easy preparation, stability, low cost, sustained and controlled release of a highly water soluble drug.
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Affiliation(s)
- S K Mehta
- Department of Chemistry and Center of Advanced Studies in Chemistry, Panjab University, Chandigarh, India.
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Huey LG. Measurement of trace atmospheric species by chemical ionization mass spectrometry: speciation of reactive nitrogen and future directions. MASS SPECTROMETRY REVIEWS 2007; 26:166-84. [PMID: 17243143 DOI: 10.1002/mas.20118] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Chemical ionization mass spectrometry (CIMS) has proven to be a powerful method for sensitive, fast time response (t approximately 1 sec) measurements of various atmospheric compounds with limits of detection (LOD) of the order of tens of pptv and lower. The rapid time response of CIMS is particularly well suited for airborne measurements and its application has largely grown out of airborne measurements in the stratosphere and upper troposphere. This work reviews some of the advances in CIMS technology that have occurred in the past decade. In particular, CIMS methods for selective measurement of reactive nitrogen species (e.g., HNO3, HO2NO2, PAN, and NH3) in the lower atmosphere (altitudes approximately 0-8 km) are described. In addition, recent developments in CIMS technology for the selective measurement of gas-phase hydroperoxides and aerosol chemical composition are briefly described.
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Affiliation(s)
- L Gregory Huey
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
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Chacko SA, Wenthold PG. The negative ion chemistry of nitric oxide in the gas phase. MASS SPECTROMETRY REVIEWS 2006; 25:112-26. [PMID: 16138298 DOI: 10.1002/mas.20060] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Nitric oxide is not only an important biological molecule with varied indispensable physiological roles but also shows interesting chemical reactivity both in gas-phase and solution phase. Even though it is a small molecule with an extremely low electron affinity, the reactivity of NO in the gas-phase is not just limited to electron-transfer or adduct formation. NO can behave both as an electrophile with closed-shell anions or as a radical with open-shell anions. Its reactivity with open-shell anions is characteristic and varied leading to interesting rearrangements. Nitric oxide anion undergoes spin-forbidden proton transfer with strong acids. Also, the ability of NO to serve both as one-electron or three-electron donor ligand can result in adduct formation or substitution reactions with transition metal complexes.
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Affiliation(s)
- Silvi A Chacko
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
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Thornton DC. Fast airborne sulfur dioxide measurements by Atmospheric Pressure Ionization Mass Spectrometry (APIMS). ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2002jd002289] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Morris RA, Miller TM, Paulson JF, Viggiano AA, Feldmann MT, King RA, Schaefer HF. Formation of CF3O− in the gas phase. J Chem Phys 1999. [DOI: 10.1063/1.478753] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Huey LG, Dunlea EJ, Lovejoy ER, Hanson DR, Norton RB, Fehsenfeld FC, Howard CJ. Fast time response measurements of HNO3in air with a chemical ionization mass spectrometer. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/97jd02214] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Asher RL, Appelman EH, Tilson JL, Litorja M, Berkowitz J, Ruscic B. A photoionization study of trifluoromethanol, CF3OH, trifluoromethyl hypofluorite, CF3OF, and trifluoromethyl hypochlorite, CF3OCl. J Chem Phys 1997. [DOI: 10.1063/1.474017] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Huey L, Lovejoy ER. Reactions of SiF5− with atmospheric trace gases: ion chemistry for chemical ionization detection of HNO3 in the troposphere. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0168-1176(96)04394-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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The kinetics of the reactions of Cl−, O−, and O2− with HNO3: Implications for measurement of HNO3 in the atmosphere. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0168-1176(95)04354-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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