Methyl ethyl ether, reaction

The addition product, C QHgNa, called naphthalenesodium or sodium naphthalene complex, may be regarded as a resonance hybrid. The ether is more than just a solvent that promotes the reaction. StabiUty of the complex depends on the presence of the ether, and sodium can be Hberated by evaporating the ether or by dilution using an indifferent solvent, such as ethyl ether. A number of ether-type solvents are effective in complex preparation, such as methyl ethyl ether, ethylene glycol dimethyl ether, dioxane, and THF. Trimethyl amine also promotes complex formation. This reaction proceeds with all alkah metals. Other aromatic compounds, eg, diphenyl, anthracene, and phenanthrene, also form sodium complexes (16,20). 

Diethoxymethane is the main product obtained at lower temperature (130 °C), whereas methyl ethyl ether, methanol, ethyl propionate and ethoxyacetic derivatives predominate at higher temperature (170 C). Diethylcarbonate, always present among the reaction products, is obtained, however, only in low yields (2-3%). 

The methoxy species was detected by a reaction with acetic acid, ethyl iodide or water (or ethanol) giving methyl acetate, methyl ethyl ether or methanol, respectively. Formates were determined using dimethylsulfate (DMS). 

The constant for the decomposition of gaseous propionic aldehyde falls away steadily below about 80 mm., that for the decomposition of diethyl ether below about 150 mm., that for the decomposition of diethyl ether below about 300 mm. Several other ethers, dipropyl ether, methyl propyl ether and methyl ethyl ether behave in a similar manner. The velocity constant for the decomposition of azomethane also diminishes but not until lower pressures are reached for example at 290° C. k at 0-259 mm. has one-fourth of its value at 707-9 mm. In several reactions, such as the racemization of pinene, and the decomposition of gaseous acetone the falling off of the velocity constant has not actually been looked for. The decomposition of azoisopropane is unimolecular down to pressures of 0-25 mm. 

Sodium bismuthate reacts with 1 (47, 52), as does BiON03 (46). Methyl exchange between Cr(II) and 1 follows second-order kinetics (55) the rate constant was 360 30M sec-1, and values for the activation parameters A H and A 5 were 15.9 0.9 kJ mol-1 and -144 J mol-1 K respectively. Ferric compounds are reported to demethylate 1 (30, 31, 37). Cupric nitrate gives no noticeable reaction by itself with 1 (46, 54), but de-methylation proceeds readily in the presence of high chloride or bromide concentrations (>2 M). Methyl chloride and methyl bromide formed as products. When ethanol was used as solvent, methyl ethyl ether also formed as product (54). An unstable intermediate CH3CuC1 may form as... 

Alkoxide ion formation is important as a means of generating a strong nucleophile that will readily form C-O bonds in SN2 reactions. Thus ethanol reacts very slowly with methyl iodide to give methyl ethyl ether, but sodium ethoxide in ethanol solution reacts quite rapidly ... 

The rate constants for the reactions between OH and a range of ethers and hydroxy ethers have been reported at 298 K233 as well as those for reactions between dimethyl ether and methyl f-butyl ether over the range 295-750 K.234 Data from the former study show deviations from simple structure-activity relationships which were postulated to arise due to H-bonding in the reaction transition states.233 The atmospheric lifetime of methyl ethyl ether has been determined to be approximately 2 days.235 Theoretical studies on the H-abstraction from propan-2-ol (a model for deoxyribose) by OH have been reported using ab initio methods (MP2/6-31G ).236 The temperature dependence (233-272 K) of the rate coefficients for the reaction of OH with methyl, ethyl, n-propyl, n-butyl, and f-butyl formate has been measured and structure-activity... 

Using the catalyst system known from the Monsanto process, Dumas et at. have been able to direct the reaction towards ethanol formation using syngas mixtures extremely rich in hydrogen [87]. As is shown in Table XII, no acetic acid and only minor amounts of acetates are formed at an H3/CO ratio of 60. Ethanol and acetaldehyde aie the main products along with considerable amounts of methyl ethyl ether. Unfortunately, the Dumas c/ at. based the yields and conversion on carbon monoxide and not on methanol. This makes the data of this interesting process difficult to compare with those of other catalyst systems. 

METHYL ETHYL ETHER (540-67-0) Flammable gas (flash point -35°F/ —37°C), Violent reaction with strong oxidizers, sulfuric and nitric acids. Incompatible with permanganates, peroxides, ammonium persulfate, bromine dioxide. May be able to form unstable peroxides in storage. Attacks some plastics, rubber, and coatings. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

It has already been shown that in sodium ethylate sodium is joined to oxygen. The simplest interpretation of the reaction just given—and the one which has proved correct—is that the ethyl group in the iodide takes the place of the sodium atom in the ethylate sodium iodide and ether are formed. The formation of the so-called mixed ethers—compounds which contain two different alkyl groups linked to oxygen—is further evidence of the correctness of this interpretation of the reaction. When sodium methylate is heated with ethyl iodide, methyl-ethyl ether is formed —... 

An example of an asymmetric induction from optically inactive monomers is an anionic polymerization of esters of butadiene carboxylic acids with (/ )-2-methylbutyUithium or with butyUithium complexed with (—)methyl ethyl ether as the catalyst. (This type of polymerization reaction is described in Chap. 4) The products, tritactic polymers exhibit small, but measurable optical rotations [78]. Also, when benzofuran, that exhibits no optical activity, is polymerized by cationic catalysts like aluminum chloride complexed with an optically active co catalyst, like phenylalanine, an optically active polymer is obtained [77]. 

Reaction of the alcoholic group in the glycol ether molecule with acetic acid yields the ester, propylene glycol methyl ether acetate, PMA. The ethylene glycol ethyl ether reaction with acetic acid gives the ester product ethylene glycol ethyl ether acetate, EEA. Several other ethylene glycol alkyl ether esters are commercially available and are included in Chapter 11. 

The reaction of OH with methyl ethyl ether has been the subject of two relative rate studies, one covering the range 276-345 K (Starkey et al., 1997) and the other one conducted at 753 K (Tranter and Walker, 2001). Data are summarized in table III-B-5. The data of Starkey et al. (1997) suggest very little temperature dependence to the rate coefficient near room temperature, although the rate coefficient clearly increases at higher temperatures. A rate coefficient of 6.3 x 10 cm molecule" s" (the average of the Starkey et al. data points) is recommended at 298 K, with an uncertainty of 50%. Further studies are required before lower temperature recommendations can be made. 

Table lll-B-5. Rate coefficients k, cm molecule" s" ) for reaction of OH with methyl ethyl ether (CH3OCH2CH3)... 

Removal of methyl ethyl ether from the atmosphere will be controlled mainly by its reaction with OH. A lifetime of about 2 days is derived, assuming an average atmospheric [OH] = 1 X 10 molecule cm". Reaction with NO3 and with Cl-atoms may be significant in some circumstances. A lifetime of about 4 days with respect to reaction with NO3 is estimated, for polluted conditions ([NO3] = 3 x 10 molecule cm ). 

Starkey, D.R, K.A. Holbrook, GA. Oldershaw, and R.W. Walker (1997), Kinetics of the reactions of hydroxyl radicals (OH) and of chlorine atoms (Cl) with methyl ethyl ether over the temperature range 274—345 K, Int. J. Chem. Kinet., 29, 231-236. 

Difluoroethanol is prepared by the mercuric oxide cataly2ed hydrolysis of 2-bromo-l,l-difluoroethane with carboxyHc acid esters and alkaH metal hydroxides ia water (27). Its chemical reactions are similar to those of most alcohols. It can be oxidi2ed to difluoroacetic acid [381-73-7] (28) it forms alkoxides with alkaH and alkaline-earth metals (29) with alkoxides of other alcohols it forms mixed ethers such as 2,2-difluoroethyl methyl ether [461-57-4], bp 47°C, or 2,2-difluoroethyl ethyl ether [82907-09-3], bp 66°C (29). 2,2-Difluoroethyl difluoromethyl ether [32778-16-8], made from the alcohol and chlorodifluoromethane ia aqueous base, has been iavestigated as an inhalation anesthetic (30,31) as have several ethers made by addition of the alcohol to various fluoroalkenes (32,33). Methacrylate esters of the alcohol are useful as a sheathing material for polymers ia optical appHcations (34). The alcohol has also been reported to be useful as a working fluid ia heat pumps (35). The alcohol is available ia research quantities for ca 6/g (1992). 

Linalool can be converted to geranyl acetone (63) by the CarroU reaction (34). By transesterification with ethyl acetoacetate, the intermediate ester thermally rearranges with loss of carbon dioxide. Linalool can also be converted to geranyl acetone by reaction with methyl isopropenyl ether. The linalyl isopropenyl ether rearranges to give the geranyl acetone. 

Anhydrous stannous chloride, a water-soluble white soHd, is the most economical source of stannous tin and is especially important in redox and plating reactions. Preparation of the anhydrous salt may be by direct reaction of chlorine and molten tin, heating tin in hydrogen chloride gas, or reducing stannic chloride solution with tin metal, followed by dehydration. It is soluble in a number of organic solvents (g/100 g solvent at 23°C) acetone 42.7, ethyl alcohol 54.4, methyl isobutyl carbinol 10.45, isopropyl alcohol 9.61, methyl ethyl ketone 9.43 isoamyl acetate 3.76, diethyl ether 0.49, and mineral spirits 0.03 it is insoluble in petroleum naphtha and xylene (2). 

Rapid, simple, quaUtative methods suitable for determining the presence of benzene in the workplace or surroundings have been utilized since the 1930s. Many early tests offered methods for detection of aromatics but were not specific for benzene. A straightforward test allowing selective detection of benzene involves nitration of a sample to y -dinitrobenzene and reaction of the resultant ether extract with an ethanoHc solution of sodium hydroxide and methyl ethyl ketone (2-butanone), followed by the addition of acetic acid to eliminate interferences from toluene and xylenes. Benzene imparts a persistent red color to the solution (87). The method is claimed to be sensitive to concentrations as low as 0.27 ppm benzene from 10 mL air samples. 

As stated previously, 3-monoethyl enol ethers can be prepared from A" -3,17-diketones and A -3,20-diketones by warming with stoichiometric amount or a large excess of ethyl orthoformate at room temperature. With 2,2-dimethoxypropane, the 3-methyl enol ether is the only reaction product even at high temperatures. 

A mixture of 17.6 grams of p-n-butoxyacetophenone, 12.1 grams of piperidine hydrochloride, 4.5 grams paraformaldehyde, 0.25 cc concentrated hydrochloric acid, 52.5 cc nitro-ethane, 7.5 cc of 95% ethanol, and 15 cc of toluene was boiled under reflux for one hour, removing water formed in the reaction by means of a condensate trap. The mixture was then cooled. The crystals which formed were collected by filtration, washed with anhydrous ether and recrystallized from methyl ethyl ketone. The crystals thus obtained, which melted at 174°-175°C, were shown by analysis to be 4-n-butoxy-beta-piperidinopropiophen-one hydrochloride. 

Prepares solution of sodium methylate by dissolving 3.9 g of sodium metal in 500 ml of methanol. Add 39.0 g of 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazeplne-2-one. Evaporate the reaction mixture to a residue and dissolve the residue in 170 ml of dimethylformamide. Add 30 g of 2,2,2-trifluoroethyl Iodide and stir at room temperature for Vi hour, then heat to 60°C to 70°C for an additional 7 hours. Add 19 g of 2,2,2-trifluoroethyl iodide and resume the heating and stirring at 60°C to 70°C for an additional 16 hours. Filter off the solids and evaporate the filtrate to a residue in vacuo. Triturate the residue with water and extract with ethyl ether. Wash the ethereal extract with water, dry over anhydrous sodium sulfate and evaporate the solvent to a residue. 

C) 4 -lodobutyl-3,4-Dimethoxybenzoate 32.5 g of 4 -chlorobutyl-3,4-dimethoxybenzoate and 19.5 g of sodium iodide (10% excess) were boiled in 150 ml of methyl ethyl ketone for 2.5 hours after cooling and filtering off the sodium chloride produced, the reaction was found not to be entirely completed boiling was then continued for another two hours the reaction mixture was cooled, and the solid filtered off and washed with 2 x 100 ml of ether. 

D) 4 -[N-Ethyi-1 "-Methyl-2 -(4" -Methoxyphenyl)Ethylamino]Butyi-3,4-Dimethoxybenzoate Hydrochloride 10.3 g of 4 -iodobutyl-3,4-dimethoxybenzoate and 11.0 g of N-ethyl-p-methoxyphenylisopropylamine (obtained by catalytic reduction of an alcoholic solution of an excess quantity (60%) of p-methoxy-phenyl-acetone, to which was added a 33% (weight-for-weight) aqueous solution of ethylamine, with Pt as a catalyst), were boiled in 200 ml of methyl ethyl ketone for 20 hours, cooled and the iodine ion was determined the reaction was found to be complete. Then the methyl ethyl ketone was evaporated in vacuo and the residue was dissolved in 300 ml of water and 30 ml of ether the layers were separated and the water layer was extracted twice more with 20 ml portions of ether. 

A mixture of 50 grams of a-dl-1,2-diphenyl-2-hydroxy-3-methyl-4-dimethylaminobutane hydrochloride, 50 grams of propionic anhydride and 50 cc of pyridine was refluxed for about 5 hours. The reaction mixture was cooled to 50°C and ethyl ether was added to the point of incipient precipitation. The hydrochloride salt of 0 -dl-l,2-diphenyl-2-propion-oxy-3-methyl-4-dimethylamlnobutane formed in the reaction precipitated upon cooling and was removed by filtration and washed with anhydrous ether. On recrystallization from a mixture of methanol and ethyl acetate, a-dl-l, 2-diphenyl-2-propionoxy-3-methyl-4-dimethyl amlnobutane hydrochloride melted at 170°-171°C. 

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