Ethyl Methyl Ether Research Articles

Energy Difference between Rotational Isomers of Methyl Ethyl Ether

Energy Difference between Rotational Isomers of Methyl Ethyl Ether

The Mercury 6(3P1) Photosensitized Decomposition of Methyl Ethyl Ether

AbstractThe mercury photosensitized decomposition of methyl ethyl ether has been studied at 55 °C and at pressures between 0.25 and 10 Torr in a static system. Some twenty products are observed at moderate conversions of which the most abundant are hydrogen and 2,3‐dimethoxyl butane. The distribution of products studied as a function of irradiation time and ether pressure is consistent with a primary process which produces an alkoxyl alkyl radical through breaking of a carbon hydrogen bond. A possible competing primary process producing alkyl and alkoxyl radicals through breaking of a carbon‐oxygen bond occurs with no more and probably considerably less than ten percent probability in this pressure range.

Reactions of methylene with ethers. Part 2.—With ethyl methyl ether

Singlet methylene reacts with methyl ethyl ether in the gas phase to yield methyl n-propyl ether, methyl isopropyl ether and diethyl ether as the major products. The relative yields † of these ethers indicate a nearly random insertion in the various carbon-hydrogen bonds. Triplet methylene reacts, under the same conditions, to give methyl isopropyl ether and diethyl ether but no methyl n-propyl ether. This difference in the reaction products of the two states of methylene has been used to estimate the ratio of singlet to triplet species reacting with the ethyl methyl ether. The effect of inert gases, of changing the methylene precursor, wavelength of the photolytic radiation, and pressure on this ratio have been studied.

Reactions of methylene with ethers. Part 1.—Dimethyl ether, methyl ethyl ether, methyl n-propyl ether, methyl-isopropyl ether, methyl-t-butyl ether and tetrahydrofuran

The reactions of methylene, produced by the photolysis of both ketene and diazomethane, with a number of simple ethers have been studied. Most of the data obtained refer to the gas phase but some liquid-phase results are also reported. Methylene in its singlet state has been found to insert in the various carbon hydrogen bonds in a near random fashion. Triplet methylene gives rise to products by attack predominantly on the carbon hydrogen bonds of carbon atom α to the oxygen atom of the ethers. Because of these differences it has been possible to estimate the percentage of singlet and triplet methylene present under various conditions. Products were obtained which correspond formally to those expected from the insertion in a carbon-oxygen bond. Except for cyclic ethers these probably result from abstraction followed by recombination reactions. Only singlet methylene appears to undergo a displacement reaction which with methyl alkyl ethers results in the formation of dimethyl ether and an olefin.

Mercury-photosensitized decomposition of dimethyl ether. Part III. The combination of radicals

As part of the study of the mercury-photosensitized decomposition of dimethyl ether, the combination of methyl radicals has been investigated in the temperature range 200 to 300 °C and at pressures between 3 and 300 mm Hg. For pressures of less than 100 mm the second-order rate coefficient for the combination of methyl radicals shows a pressure dependence. The pressure dependence agrees qualitatively with that observed by others, but occurs at somewhat higher pressures. Calculations for the Kassel equation using the Arrhenius parameters for ethane decomposition and fitted to the pressure dependence of the methyl radical combination show that the number of effective modes for ethane decomposition is 8 or 9. Carbon dioxide was found to be a quite ineffective third body for energy transfer. The results for the mercury-photosensitized decomposition of dimethyl ether have also been analyzed to obtain information about the combination of methyl radicals with methoxymethyl radicals. The combination of these radicals becomes pressure dependent at pressures less than about 15 mm. Kassel integrations based on the rate constant [Formula: see text]for the unimolecular decomposition of methyl ethyl ether at the C—C bond, and fitted to the observed pressure dependence of the combination reaction, lead to s = 10 for these reactions.The rate constant for the abstraction of a hydrogen atom by a methyl radical from dimethyl ether was found to be [Formula: see text]

Vibrational analysis of ten simple aliphatic ethers: Spectra, assignments, valence force field and molecular conformations

A vibrational analysis of ten simple aliphatic others has been carried out. Vibrational spectra (infrared for all, Raman for some) have been measured, bands have been assigned and a valence force field has been derived. The ethers studied are: dimethyl ether, methyl ethyl ether, diethyl ether, 1:2-dimethoxyethane, 1:4-dioxane, tetrahydropyran, methyl isopropyl ether, ethyl isopropyl ether, di isopropyl ether and 2:5( ρρ)-dimethyldioxane(1:4). The valence force field contains seventy-six parameters. Forty-three of these were not adjusted but were assigned fixed values equal to those of analogous force constants determined from earlier studies on the paraffins; the remaining thirty-three were adjusted using 204 frequencies from the observed spectra. After refinement there was an average error of 10.7 cm −1 between observed and calculated frequencies. For six others rotational isomerism is possible. In these cases the molecular conformation in the annealed solid has been established. For these samples in the liquid state it was sometimes possible to identify more than one conformation.

Reaction of? aminoethers with triethyl phosphite

1. The reactions of triethyl phosphite with diethylaminomethyl methyl, diethylaminomethyl ethyl, diethylaminomethyl propyl, diethylaminoethyl butyl, and methylphenylaminomethyl ethyl ethers in the presence of acetic acid and with diethylaminomethyl ethyl ether hydrochloride and diethylaminomethyl ethyl ethiodide have been studied. 2. In the case of a salt-forming agent having a labile hydrogen atom, rupture of a C-O bond in the α-aminoether takes place with the formation of only diethyl diethylaminomethylphosphonate. Salt-forming agents of the type of alkyl halides lead to the formation of diethyl alkoxymethylphosphonates.

Hexachlorophene Deposition in Human Stratum Corneum

Special vehicles such as dimethylacetamide (DMAC), dimethylsulfoxide (DMSO), and methylethylether (MEE) greatly enhance the deposition of hexachlorophene in the horny layer and increase the bacteriostatic effectiveness of the horny layer so treated.

Measurements of heats of combustion by flame calorimetry. Part 2.—Dimethyl ether, methyl ethyl ether, methyl n-propyl ether, methyl isopropyl ether

The first page of this article is displayed as the abstract.

STUDIES ON THE SOLVENT FOR DEGREASING PROCESS OF RAW WOOL. PART 4

The author has investigated which of the removing actions are better flowing-out and the steeping methods for the yolk of greasy wool, from the results reported in Parts 2 and 3. It was found that the flowing-out method was excellent for every solvent. In the fourteen kinds of solvent used for experiment, methylene chloride was found the best solvent and the next carbon tetrachloride for removing the yolk. Kerosene was unexpectedly excellent too. Acetone, methyl ethyl ketone, anon and ethyl ether were extremely inferior.The author has also made the experimental measurements concerning the fatigue property of liquor that was accompanied by repetition of degreasing treatment for the eight kinds of typical solvent. The fatigue property of each solvent was very remarkable in the case of the flowing-out method, but one was comparatively little in the case of the steeping method.

The reaction of methylene with ethers

AbstractLittle quantitative work has been published on the reactions of methylene with ethers. Doering et al1 W. E. Doering, L. H. Knox, and M. Jones, J. Org. Chem. 24, 137 (1959) studied the reaction of methylene with diethyl ether and found ethyl propyl ether and ethyl isopropyl ether with relative yields 55.5 : 45.5. This implies that the methylene inserts 1.2 times as rapidly in the secondary C‐H bonds as in the primary C‐H bonds. They found no evidence for any carbon rearrangement of a diethyl ether‐methylene ylid but indicated that a hydrogen rearrangement from such an “ylid” would lead to deviations from statistical attack in the required direction. Franzen and FikentscherV. Franzen, and L. Fikentscher, Annalen 617, 1, (1958). were able to show, directly, by the use of labelled compounds that none of the insertion products arose by a carbon skeleton rearrangement. They also showed that in the reaction of methylene with diethyl ether some methyl ethyl ether is formed but no quantitative data was obtained.

Penthrane

Methoxyflurane (Penthrane - Abbott) is a non-flammable halogenated ethyl methyl ether which has been recently introduced as an inhalation anaesthetic. A detailed discussion of its properties appeared in the Lancet on August 31, 1963 (p. 446).

Student preparation and manipulation of a gas—Methyl ethyl ether

Student preparation and manipulation of a gas—Methyl ethyl ether

Termination Products and Processes in the Pyrolysis of Dimethyl Ether

Termination processes in the pyrolysis of dimethyl ether studied by trace product analysis using gas—liquid chromatography revealed the presence of methyl ethyl ether, 1,2-dimethoxyethane, and methanol. These ethers had been predicted in the work of Benson and Jain by including CH3OCH2 as a chain terminator, and their identification is evidence for the reaction CH3OCH2→CH3+CH2O being an energy transfer process in its second-order region. Methanol was also predicted from the reactions of CH3O or CH2OH. Quantitative measurement of the trace termination products were made to obtain yields for MeOEt, Me2O, and C2H6, which could be used to calculate the rate constant ratio k2′/k2 for the attack by CH3 on MeOEt compared to Me2O. When the steady state is approached from both sides, k2′/k2 ranges from 4–12 and is greater than unity, as expected. A reasonable difference in activation energy of about 2–4 kcal is estimated for these reactions. However, the MeOEt gas chromatography peak was broad when resolved from Me2O resulting in loss of precision and together with the required estimates in the steady-state equation (7) severely limit the usefulness of trace termination product analysis in determining new rate constants. Ethane was measured and compared to a calculated steady-state value. Because of attack on the ethane and the disappearance of radicals by other termination processes the ratio of the Me2O decomposed to the C2H6 found is not as good a measure of the chain length as those calculated from the rate law.

Methoxyflurane as an anesthetic for neurological surgery.

HE most favorable physiologic conditions for anesthesia in neurosurgery are provided bv diethyl ether, because it is least depressant to respiratory function and maintains a stable cardiovascular system. The definite hazard of fire or explosion, particularly in the presence of the electrocautery, has influenced many neurosurgeons to accept anesthetic agents and techniques which, while providing nonflammability, nevertheless introduce the less favorable physiologic conditions inherent in the employment of multiple drug techniques. The main ingredient of the nonexplosive technique currently preferred by many neurosurgeons is nitrous oxide. However, because of its low potency there may be insufficient analgesia for many procedures, there is an increased hazard of hypoxia, and the patient frequently reacts on the endotracheal tube. In an attempt to compensate for the inadequacies of nitrous oxide, anesthetists have added intravenous drugs such as barbiturates, narcotics, and muscle relaxants, as well as inhalation anesthetics such as trichloroethylene (Trilene | Trimar | or halothane (Fluothane| Each of these supplements may produce unwanted effect on respiration or circulation. In an attempt to find a nonflammable anesthetic agent as innocuous as nitrous oxide but with greater potency, Van Poznak and Artusio 1-4 in 1956 began screening a number of fluorinated hydrocarbons and fluorinated ethers.* The most useful compound so far examined has been given the generic name methoxyflurane. It is 1,1-difluoro e,e-dichloro ethyl methyl ether, with the following structural formula: CH3-O-CF2CHC12. It is a clear, colorless liquid of characteristic odor. The boiling point is 103~ and the vapor pressure at e0~ is e5 mm. Hg. It is stable in the presence of light, soda, lime, and Baralyme | Presently available samples have dibenzylamine 0.01 per cent added as a stabilizer. At room temperature it is nonflammable in any mixture of air or oxygen. Pharmacologically, its behavior is in many ways similar to that of diethyl ether. Methoxyflurane can be administered by any technique used for diethyl ether, including open drop, semiclosed circle, and closed circle. A special vaporizer is not needed. It is compatible with other agents such as * Many of these compoumls were synthesized in tim laboratories of the Dow Chemical Company.

Vibrational Spectra of Methylethyl Ether and Diethyl Ether

脂肪族工一テル類の振動スペクトルの研究の一環としてメチルエチルエーテルおよびジエチルエーテルについて,液体のラマン効果およびフッ化リチウム・岩塩・臭化カリウム・臭化セシウム各プリズム領域における気体ならびに四塩化炭素溶液の赤外線吸収を測定した。ジメチルエーテルのスペクトルおよびその帰属を参照してとくにメチルエチルエーテルについて振動スペクトルの経験的帰属を行なった。

The Retentivity of Charcoals by the Approximate Isotherm Method. The Effect of Moisture on the Retentivity of Methyl Ethyl Ether, Neopentane and Methanol.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Retentivity of Charcoals by the Approximate Isotherm Method. The Effect of Moisture on the Retentivity of Methyl Ethyl Ether, Neopentane and Methanol.D. H. Volman and G. J. DoyleCite this: J. Phys. Chem. 1952, 56, 2, 182–185Publication Date (Print):February 1, 1952Publication History Published online1 May 2002Published inissue 1 February 1952https://doi.org/10.1021/j150494a007RIGHTS & PERMISSIONSArticle Views18Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (429 KB) Get e-Alerts

A new synthesis of asaronic acid and aldehyde and their derivatives

Asaronic acid is conveniently prepared from 4-O-methyl-β-resorcylic acid and isovanillic acid by oxidatron with alkaline persulphate and subsequent methylation. Useful partial methyl ethers and mixed methyl-ethyl ethers are also made by adopting this method. Similarly asarylic aldehyde is obtained from 4-O-methyl-β-resorcylic aldehyde and isovanillin.

Some important ethyl and ethyl-methyl ethers of flavonols

The use of ethylation in the study of naturally occurring glycosides and partial methyl ethers of hydroxy flavones is discussed. This procedure renders the work simpler and more definite. Starting from ω-ethoxy res-and phloracetophenones, the preparation of mixed ethyl methyl ethers of the flavonols, fisetin, kaempferol, and quercetin, with an ethoxyl in the 3-position and methoxyls in the other positions, is described and it is shown that these compounds are useful in the study of the 3-glycosides of these flavonols. The case of rutin has been used as a typical example.

Reactions of Free Radicals with Organic Compounds Containing Atoms with Unshared Electron Pairs

An experimental test for the reaction CH3+CH3OCH2CH3→CH3OCH3+CH3CH2 was made by decomposing methyl ethyl ether both alone and in presence of azomethane, and examining the products for dimethyl ether; none was detected, and if this reaction occurs at all it is only to the extent of a very few percent. A similar test for the reaction CH3+CH3CH2CH2NH2→CH3NH2 +CH3CH2CH2 was made by decomposing pure n-propylamine in a flowing system, but this also gave a negative result. The products formed in the promoted decomposition of dimethyl ether were found to be essentially the same as those formed in the normal decomposition.