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1.
Reactions of perfluoropropylene and its oligomers with acetone oxime in the presence of a base afford perfluoroalkyl and/or perfluoroalkenyl ethers of acetone oxime. When heated to 100 °C, the 3-perfluoro-2-methyl-2-pentenyl ether of acetone oxime (3) is quantitatively converted to 4-hydroxy-3-methyl-5,5-bistrifluoromethyl-4-pentafluoroethyl-1-pyrroline (4), the structure of which was established by X-ray diffraction analysis. A convenient one-stage synthesis of perfluoro-3-isopropyl-4-methyl-3-penten-2-one (7) was proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1068–1072, June, 1994. 相似文献
2.
Acetone plays an important role in the chemistry of both the atmosphere and the ocean, due to its potential effect on the
tropospheric HOx (= HO + HO2) budget, as well as its environmental and health effects. We discuss the development of a mobile, sensitive, selective, economical
and facile method for the determination of acetone in seawater. The method consists of derivatizing acetone to its pentafluorobenzyl
oxime using 1,2,3,4,5-pentafluorobenzylhydroxylamine (PFBHA), followed by solid-phase microextraction (SPME) and analysis
by gas chromatography/mass spectrometry (GC/MS). A detection limit of 3.0 nM was achieved. The buffering capacity of seawater
imposes challenges in using the method’s optimum pH (3.7) on seawater samples, requiring calibration standards to be made
in buffered salt water and the acidification of seawater samples and standards prior to extraction. We employed the technique
for analysis of selected surface seawater samples taken on the Nordic seas during the ARK-XX/1 cruise (R.V. Polarstern). An upper limit of 5.5–9.6 nM was observed for acetone in these waters, the first acetone measurements reported for far
North Atlantic and Arctic waters.
Simplified schematic of transformations of organic compounds at the atmosphere–ocean interface 相似文献
3.
Nadine Metz 《European Polymer Journal》2007,43(4):1202-1209
Acetone oxime acrylate has been synthesized as a new active ester monomer. Free radical polymerization yielded a reactive polymer soluble in various organic solvents, such as chloroform, dioxane, DMSO, acetone, methanol, dichloromethane, DMF, and ethanol. Controlled radical polymerization of acetone oxime acrylate was successfully conducted using the RAFT, NMP and Iniferter method. Partly polymer analogous reaction with N-isopropylamine resulted in the reactive copolymer poly(N-isopropylacrylamide-co-acetone oxime acrylate), which featured a lower critical solution temperature (LCST) of 61 °C in water. Further, the reactivity of the copolymer was exemplary proven by complete reaction with ammonia yielding poly(N-isopropylacrylamide-co-acrylamide), which does not possess a LCST. 相似文献
4.
Deng C Li N Wang X Zhang X Zeng J 《Rapid communications in mass spectrometry : RCM》2005,19(5):647-653
In the current work, a simple, rapid, accurate and inexpensive method was developed for the determination of acetone in human blood. The proposed method is based on derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA), followed by headspace liquid-phase microextraction (HS-LPME) and gas chromatography/mass spectrometry (GC/MS). In the present method, acetone in blood samples was derivatized with PFBHA and acetone oxime formed in several seconds. The formed oxime was enriched by HS-LPME using the organic solvent film (OSF) formed in a microsyringe barrel as extraction interface. Finally, the enriched oxime was analyzed by GC/MS in electron ionization (EI) mode. HS-LPME parameters including solvent, syringe plunger withdrawal rate, sampling volume, and extraction cycle were optimized and the method reproducibility, linearity, recovery and detection limit were studied. The proposed method was applied to determination of acetone in diabetes blood and normal blood. It has been shown that derivatization with HS-LPME and GC/MS is an alternative method for determination of the diabetes biomarker, acetone, in blood samples. 相似文献
5.
The reaction of aryl diazonium salts containing electron-withdrawing substituents in the aromatic ring with acetone oxime leads to the formation of nitrogen-containing products instead of the expected functional derivatives of 1-alkyl-3-aryltriazene 1-oxides. The structure of these products is a function of the number and chemical nature of the substituents in the diazo component.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1911–1913, August, 1992. 相似文献
6.
Christian-Robert Raddatz Maria Allers Ansgar T. Kirk Stefan Zimmermann 《International Journal for Ion Mobility Spectrometry》2018,21(3):49-53
Measuring a mixture of acetone and perdeuterated acetone (acetone-d6) with an ultra-high resolution drift time ion mobility spectrometer (resolving power of Rp?=?235) and ultraviolet ionization (10.6 eV) at ambient pressure reveals three separated peaks. Two of the peaks can easily be associated with acetone and perdeuterated acetone. In a former publication several findings indicated an exchange of a methyl group and the formation of a H3COCD3 related peak. In this work the formed ion species were analyzed with a high resolution drift time ion mobility time of flight mass spectrometer. The mass spectra clearly show the formation of three proton-bound dimer peaks whereas the peak between acetone and acetone-d6 is a proton-bound mixed dimer consisting of one acetone and one acetone-d6 molecule. 相似文献
7.
Ring-chain tautomerism of acetone N-methylated thiosemicarbazones was studied by nmr spectroscopy. Acetone thiosemicarbazone, acetone 2-methylthiosemicarbazone, and acetone 4-methylthiosemicarbazone exist as chain forms in DMSO-d6 and ring forms in deuteriotrifluoroacetic acid. However, the compound obtained by reaction of acetone with 2,4-dimethylthiosemicarbazide exists only as the ring form 3,5,5-trimethyl-1,3,4-thiadiazolidine-2-methylimine both in DMSO-d6 and in deuteriotrifluoroacetic acid, due to steric hindrance of the three methyl groups. 相似文献
8.
V. Aviyente M. Iraqi T. Peres C. Lifshitz 《Journal of the American Society for Mass Spectrometry》1991,2(2):113-119
Ion clusters were formed in a temperature-variable high-pressure ion source from neat acetone and acetone/water mixtures and subjected to tandem mass spectrometry studies-unimolecular and collisionally activated mass-analyzed ion kinetic energy spectroscopy. The predominance of water loss from H+(H20)(A) l=3, where A = acetone, suggests that the solvation sphere around H3O+ does not close at l = 3, contrary to the case of acetonitrile or dimethyl ether. The results may be interpreted in terms of suggested ion structures which involve isomerization enroute to dissociation. The virtual absence of H/D scrambling in the collisionally activated dissociation of H3O+(DA)3, DA =acetone-d 6, and of D3O+(A)3 means that if enolization takes place, it is a rate-determining step in an irreversible isomerization. The stability of H+(H2O)(A)3 is a dominant factor in the observation of acetone loss from H+(H20)(A)4. 相似文献
9.
Conclusions The efficient photolysis of acetone proceeds upon the photoexcitation of the donor-acceptor complex of acetone and CCl4 by light with 300 > < 330 nm with the formation of chloroketones and CHC13 as the major products. A mechanism was proposed for the photolysis of acetone in the presence of CCl4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2601–2603, November, 1987. 相似文献
10.
Milligram amounts of permanganate can be titrated with resacetophenone oxime (4-acetylresorcinol oxime) as a reducing titrant in the presence of phosphoric acid (0.5 M). The stoichiometry between permanganate and the oxime is 3:1 (MnO4-:oxime). The titration is successful in the presence of large amounts of dichromate or vanadate or moderate amounts of cerium(IV). 相似文献
11.
Deoximation in metal chloride ionic liquids based on 1‐alkyl‐3‐methylimidazolium and triethylene ammonium cations, such as AmimBr(Cl)‐MClx(A=ethyl, butyl, benzyl; M=Al, Fe, Cu, Sn and Zn; x=2, 3) and Et3NHCl‐FeCl3 were investigated under mild conditions. Ferrate chloride ionic liquid was proved to be an effective catalyst for deoximation of cyclohexanone oxime, exhibiting high conversion of oximes and selectivity to cyclohexanone. Good performance for the deoximation of other oximes such as salicylald oxime, acetone oxime, benzophenone oxime, 4‐nitrobenzald oxime, acetophenone oxime, 2‐chlorobenzaldehyde oxime, Acetald oxime, 2‐butanone oxime and (1R)‐camphor oxime was also achieved with bmimBr‐FeCl3 as catalyst and solvent. The deoximation was determined to carry out via acid‐catalytic hydrolysis and the reaction mechanism was proposed. 相似文献
12.
Dodonov V. A. Gushchin A. V. Gor"kaev D. A. Fukin G. K. Starostina T. I. Zakharov L. N. Kurskii Yu. A. Shavyrin A. S. 《Russian Chemical Bulletin》2002,51(6):1051-1057
The reactions of triphenylantimony or trimethylantimony with tert-butyl hydroperoxide in the presence of acetone oxime, acetophenone oxime, cyclohexanone oxime, or benzaldehyde oxime afforded monomeric triorganoantimony oximates Ph3Sb(ON=CMe2)2, Ph3Sb(ON=CMePh)2, Ph3Sb[ON=C(CH2)5]2, Ph3Sb(ON=CHPh)2, and Me3Sb(ON=CMe2)2 in 87—96% yields. X-ray diffraction analysis demonstrated that Ph3Sb(ON=CMe2)2 and Ph3Sb(ON=CHPh)2 have trigonal-bipyramidal structures. An analogous reaction with dimethylglyoxime gave rise to polymeric triphenylantimony dioximate in 96% yield. The reaction with butane-2,3-dione monoxime yielded chelate cyclic bis(triphenylantimony) oxides. 相似文献
13.
This paper describes the development of a method for the determination of μg quantities of beryllium using acetyl acetone. This reagent is first used to isolate the beryllium, after interfering elements have been complexed with ethylene diamine tetra-acetic acid. The beryllium is then determined absorptiometrically as the acetyl acetone complex using radiation of wavelength 2950 A. The method will detect 0.25 μg of beryllium with certainty and determine larger amounts with a precision of about ± 5 per cent. 相似文献
14.
M. Latasa K. van Lenning J. L. Garrido R. Scharek M. Estrada F. Rodríguez M. Zapata 《Chromatographia》2001,53(7-8):385-391
Summary RPHPLC methods for analysis of photosynthetic pigments (chlorophylls and carotenoids) usually require addition of water to
methanol or acetone extracts to prevent distortion of early-eluting peaks corresponding to the more polar compounds. In this
work we have investigated the short-(<2 min) and long-term (up to 48 h) effect of adding water to acetone and methanol extracts
from two marine phytoplankton species,Emiliania hyxleyi andDunaliella tertiolecta. Solvent extracts were prepared and separated into fractions that were subsequently diluted with water to 90%, 80%, 70%,
60%, 50%, and 40% for methanol, and the same range extended to 30% and 20% for acetone. Changes in pigment concentration with
time were followed spectrophotometrically and chromatographically. Losses of pigments as a result of precipitation were clearly
observed immediately after dilution of acetone extracts to 60% or less and methanol extracts to 80% or less. For chlorophyll
a the most substantial losses were recorded for 50% acetone (up to 27% decrease) and for 70% methanol (31% decrease). This
effect increased considerably with time. Only for 90% and 80% acetone were the initial concentrations of all the pigments
unchanged after 24h, and even up to 48 h. In contrast, more than 60% and 57% of the initial amounts of chlorophyll a were
lost after 24 h in 50% acetone and 70% methanol extracts, respectively. These losses increased to 83% and 60% after 48 h.
There was a clear correlation between the polarity of a pigment and the polarity of the solvent at which maximum precipitation
occurred. Losses of pigment from pure acetone and methanol extracts with time were also observed, although we attribute these
to pigment degradation rather than precipitation. Some of the losses occurring with time can be avoided by use of autosamplers
in which the sample can be mixed with water immediately before injection. 相似文献
15.
A pyridine-based macrocycle with a polyether chain has been designed and synthesized. The macrocycle shows strong binding for acetone involving both conventional and unconventional hydrogen bonds. The acetone in the cavity is exchangeable in CHCl3 by urea. This has been studied thoroughly by 1H NMR, 13C NMR, mass and X-ray analyses. 相似文献
16.
Kinetic studies are reported for the electrophilic amination of substituted phenylmagnesium bromides and CuCN‐catalyzed phenylzinc chlorides with acetone O‐(2,4,6‐trimethylphenylsulfonyl)oxime in tetrahydrofuran at reflux temperature and at room temperature respectively. Substituent effects were determined by competition experiments. Rate data are analyzed via Hammett relationships to support the proposed mechanisms for the substitution of these organometallics with an electrophilic amino transfer reagent. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
17.
The kinetics of the pyridine catalyzed hydrogen exchange of 1,1,1-trifluoroacetone in 50% D2O-dioxane have been measured using 1H-NMR. Rates of hydrogen exchange of acetone were also measured under comparable conditions and the rate of deuterium uptake by trifluoroacetone was found to exceed that of acetone by a factor of 1700 at 25°C. However trifluoroacetone is known to be extensively hydrated under these conditions. The hydrogen exchange of trifluoroacetone is interpreted as most probably proceeding through proton abstraction by pyridine from the free ketone to form the enolate followed by deuteration on carbon, with the rate of proton abstraction from trifluoroacetone exceeding that of acetone by a factor of 105 to 106. Other possibilities are also considered. 相似文献
18.
Harry R. Chobanian Ping Liu Marc D. Chioda Yan Guo Linus S. Lin 《Tetrahedron letters》2007,48(7):1213-1216
We report an expedient method for the heteroarylation of acetone under tin-free conditions. The coupling is performed using the commercially available enol silane of acetone (2-trimethylsilyloxypropene) and a corresponding aryl bromide, chloride or triflate under microwave-assisted conditions, with tris(dibenzylideneacetone)dipalladium (Pd2(dba)3) or palladium acetate (Pd(OAc)2) and 2-(2′,6′-dimethoxybiphenyl)dicyclohexylphosphine (S-Phos) as the catalyst system. 相似文献
19.
V. V. Borovik V. M. Vorotyntsev G. I. Golodets 《Theoretical and Experimental Chemistry》1988,24(1):107-110
The temperature dependences of the rate of oxidation of acetone vapors by oxygen on oxide surface catalysts: V2O5, Co3O4., MoO3 and TiO2 (rutile), and the industrial catalyst VKSh were determined. A series of the catalytic activity of the above surface catalysts was established. The relationship between the catalytic properties of the oxides in the oxidation of acetone and their redox and acid-base characteristics was analyzed. The catalytic activity of the oxides in the oxidation reaction of acetone and methanol were compared.Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 24, No. 1, pp. 114–117, January–February, 1988. 相似文献
20.
Abstract— Ultraviolet (u.v.) irradiation of solutions of benzhydrol in acetone leads to formation of -2-propanol, benzpinacol and some benzophenone, apparently from the free radicals (CH3)2COH, II, and (C6H5)2COH, I. 2-Propanol is formed more rapidly and benzophenone is formed to a much larger extent and persists longer when the solution contains mesityl mercap-tan, as radical II is reduced by mercaptan and radical I is oxidized by thiyl radical. The same hydrogen atom transfer reactions, which retard by a repair mechanism the photoreduction of benzophenone by 2-propanol, accelerate and alter the course of photoreduction of acetone by benzhydrol. Irradiation of acetone leads to 2-propanol, and this is formed more rapidly in the presence of mercaptan. Irradiation of benzophenone in acetone leads to no apparent reaction. The courses of reaction of the several systems are discussed. 相似文献