Ethers methyl t-butyl

Water Less than 0.02% by Karl Fischer titration 

Refractive index 1.3690 + 0.0010 at 20 C Boiling range 55-56 C Residue Less than one mg/1 Purity Greater than 99.0% by gc analysis Peroxida Less than one mg/1 as H2O2 

Elactron capture gc No residue peaks greater than 10 ng/1 as heptachlor epoxide. 

Refractive Index 1.4241 0.0005 at 20 C Bolling range 40-41 C Residue Less than one mg/1 

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To a solution of m-ethyl cinnamate (44, 352 mg, 85% pure, 1.70 mmol) and 4-phenylpyridine-A-oxide (85.5 mg, 29 mol%) in 1,2-dichloromethane (4.0 mL) was added catalyst 12 (38.0 mg, 3.5 mol%). The resulting brown solution was cooled to 4°C and then combined with 4.0 mL (8.9 mmol) of pre-cooled bleach solution. The two-phase mixture was stirred for 12 h at 4°C. The reaction mixture was diluted with methyl-t-butyl ether (40 mL) and the organic phase separated, washed with water (2 x 40 mL), brine (40 mL), and then dried over Na2S04. The drying agent was removed by filtration the mother liquors concentrated under reduce pressure. The resulting residue was purified by flash chromatography (silica gel, pet ether/ether = 87 13 v/v) to afford a fraction enriched in cis-epoxide (45, cis/trans . 96 4, 215 mg) and a fraction enriched in trans-epoxide cis/trans 13 87, 54 mg). The combined yield of pure epoxides was 83%. ee of the cis-epoxide was determined to be 92% and the trans-epoxide to be 65%. 

United States, methanol derived from natural gas as a fuel additive is a promising future market. Methanol has neither the environmental problems of methyl-t-butyl ether (MTBE), nor the evaporating qualities of ethanol. 

Figure 9.15. MTBE, methyl t-butyl ether, a common octane booster in gasoline, has an octane number of 116. Other boosters are ETBE (ethyl t-butyl ether RON = 118) and TAME (t-amyl methyl ether RON = 111).

Estimate the heat of vaporisation of methyl-t-butyl ether, at 100 °C. 

METHYL-1-BUTANOL 2-METHYL-2-BUTANOL 2 2-DIMETHYL-l-PROPANOL ETHYL PROPYL ETHER METHYL-T-BUTYL ETHER BUTYLMETHYL ETHER... 

The pH of the reaction stream was adjusted to neutral and the dark stream was washed with methyl-t-butyl ether to remove neutral organic impurities. The major impurity observed in the MTBE wash is phenyl oxazole formed by de-iodination of the starting iodoxazole. Phase separation of this wash is a difficult one due to the dark color of the reaction stream. 

The dwell time was 200 msec for the analytes and 100 msec for the IS. At least 500 extracted samples were injected onto each column without any column regeneration. No solvent evaporation and reconstitution steps were involved. Ethyl acetate was preferred over methyl t-butyl ether (MTBE) because MTBE caused pulp-up of the mat. Six blank plasma lots were tested for matrix interference and none was detected in the analyte or IS region. When 100 ng/mL of the analytes were spiked into the blank plasma samples, the relative standard deviations were 1.0 and 1.5% for omeprazole and its metabolite, respectively. Precision and accuracy figures are given in Table 1.9. 

Methanol Styrene Methyl t-butyl ether Ethylbenzene Benzene Vinyl chloride Dichloroethylene Propylene Ethylene... 

Leaded fuels are now banned across Canada. In unleaded gasoline, simple organic compounds are added instead of lead compounds. These octane-enhancing compounds include methyl-t-butyl ether, t-butyl alcohol, methanol, and ethanol. Like lead catalysts. 

BUTACRACKEVG A process for converting Ao-butanes to ixo-butene, which can then be converted to gasohne-blending components such as methyl t-butyl ether. Developed by Kinetics Technology International. 

MRU [Methanol recovery unit] A process for removing methanol from the unreacted components from the synthesis of methyl t-butyl ether. It uses selective adsorption on multiple beds of a zeolite such as 4A. Developed by Union Carbide Corporation and now licensed by UOP as of 1992, eight units had been licensed. See also ORU. 

Polynaphta Essence A process for making a linear olefin fraction for making methyl t-butyl ether to use as a fuel additive. Developed by IFP in 1996 replacing UOP s Catpoly process. 

Alkanes pentane, hexane, heptane, cyclohexane Chlorinated solvents chloroform, dichloromethane, 1,2-dichloroethane Ethers diethyl ether, methyl-t-butyl ether, diisopropyl ether Esters ethyl acetate, butyl acetate Long-chain alcohols butanol, octanol Aromatics benzene, toluene, xylene Alkanes pentane, hexane, heptane, cyclohexane Diethyl ether... 

In 1984 methyl t-butyl ether (MTBE) broke into the top 50 for the first time with a meteoric rise in production from 0.8 billion lb in 1983 to 1.47 billion lb in 1984 to be ranked 47. In 1990 it was 24 with production over 6 billion lb, and in 1995 it was 12 at 18 billion lb. A full discussion of the current economic status of MTBE is given in Chapter 7, Section 4 as the important gasoline octane enhancer. That is its only major use. MTBE is manufactured by the acid catalyzed electrophilic addition of methanol to isobutylene. 

Ammonia Derivatives Methyl t-butyl ether -Butyraldehyde Dimethyl terephthalate Methanol Formaldehyde Acetic acid... 

Isobutylene now finds considerable use in producing methyl t-butyl ether (MTBE) by reacting it with methanol,... 

The additives used in oxygenated gasoline are alcohols and ethers, the most common of which are ethanol (ethyl alcohol grain alcohol) and methyl t-butyl ether (MTBE). Two less commonly used additives are ethyl t-butyl ether (ETBE) and t-amyl methyl ether (TAME). The chemical structures of these four additives are shown in the diagram on page 24. 

Recent developments and concern over the control of fuel exhaust emissions have led to the increased use of combustion system detergents, oxygenates and cetane improvers in fuel. Oxygenated blend components such as ethanol, methyl t-butyl ether (MTBE), ethyl t-butyl ether (ETBE), and /-amylmethyl ether (TAME) are also used to help limit the exhaust emissions from fuel. 

Molecular sieves of various grades are very favourite drying agents, but they must not be used indiscriminately. Nitroalkanes must not be dried with them (Bretherick, 1979), and there are reports of the formation of new (and presumably unwanted) compounds under the influence of molecular sieves from 1,1,1-trichloroethane, acetone, and methyl t-butyl ether (Perrin, Armarego and Perrin, 1983). 

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