Methyl rm-butyl ether

The area under a peak is proportional to the number of hydrogens contributing to that peak. For example, in the methyl rm-butyl ether spectrum (Figure 13-19), the absorption of the ferf-butyl protons is larger and stronger than that of the methoxy protons because there are three times as many rm-butyl protons as methoxy protons. We cannot simply compare peak heights, however the area under the peak is proportional to the number of protons. 

Precision—The precision of these test methods was determined by statistic analysis of interlaboratory test results. Twelve laboratories analyzed in duplicate eight different samples, providing a total of thirteen data sets. One laboratory us two different test methods. The breakdown on data sets by test method is Test Method A, three Test Method B, two Test Method C, three Test Me od D, five. The statistical analysis was performed on the set of 13 data sets because the reductive pyrolysis technique is common to all four test methods. Separate statistics were not determined for individual test methods. The sample set included anhydrous methanol and gasoline stocks that were spiked with one or more of the following isobutanol, n-butanol, sec-butanol, tfrt-butanol, di-isopropyl ether, ethanol, ethyl ten-butyl ether, methanol, methyl rm-butyl ether, n-propanol, isopropanol, tert-amyl methyl ether. 

Shih C-C, ME Davey, J Zhou, JM Tiedje, CS Criddle (1996) Effects of phenol feeding pattern on microbial community structure and cometabolism of trichloroethylene. Appl Environ Microbiol 62 2953-2960. Somsamak P, HH Richnow, MM Haggblom (2005) Carbon isotope fractionation during anaerobic biotransformation of methyl ferf-butyl ether and ferf-amyl methyl ether. Environ Sci Technol 39 103-109. Somsamak P, RM Cowan, MM Haggblom (2001) Anaerobic biotransformation of fuel oxygenates under sulfate-reducing conditions. EEMS Microbiol Ecol 37 259-264. 

Other ethers, like methyl-rerf-butyl ether (MTBE) and ethyl-rm-butyl-ether (ETBE) have been used as additives instead of aromatic compounds in fuels to... 

In rm-butyl methyl ether at 55 C the chiral 3//-azepine 13 is in equilibrium with the achiral 3//-isomer 27.291... 

Decarboxylation of 117 was effected by treatment of 117 with LiCl in hot, aqueous HMPA at 105 °C providing 118 as a mixture of diastereomers that were separated and carried forward individually. Protection of the secondary amide group as the corresponding methyl lactim ether was accomplished by treating 118 with trimethyloxonium tetrafluoroborate in dichloromethane that contained cesium carbonate. Next, the indole nitrogen atom was protected as the corresponding Boc derivative by treatment with dicarbonic acid bis(rm-butyl)ester in the presence of DMAP and the silyl ether was removed with tetrabutylammonium fluoride to provide diol 119 in 52-78% overall yield from 118. Selective conversion of the allylic alcohol to the corresponding... 

Church, C. D., J. F. Pankow, and P. G. Tratnyek, Hydrolysis of rm-butyl formate Kinetics, products, and implications for the environmental impact of methyl fe/r-butyl ether. Environ. Sci. Technol., 18,2789-2796 (1999). 

The preparation of /m-butyl ethers requires a large excess of isobutene (bp -6.9 °C) and the inconvenience and potential hazard of a pressure vessel or a sealed tube in some cases, ten-Amyl (T m) ethers have the same lability as tert-butyl ethers towards acids, and they are prepared the same way, by reaction of the alcohol with 2-methyl-l-butene (bp 31 °C) in the presence of trifluoroborane etherate, but they require only a slight excess of the reagent [Scheme 4.128].228 Deprotection of rm-butyl and fer/-amyl ethers can be accomplished by treatment with a catalytic amount of TBSOTf. When a stoichiometric... 

The enol ether is dissolved in 25 mL of rm-butyl methyl ether/mmol of alkene, and treated with 0.5-1.0 equiv of a-chloroacetophenone oxime. Then 6-10 equiv of freshly ground anhyd Na,C03 are added and the mixture is stirred for 6-10d at 20°C. The progress of the reaction is monitored by TLC. Filtration through a short pad of Celite followed by evaporation provides the crude 1,2-oxazines which are purified by column chromatography (aluminum oxide III, neutral, pentane/fert-butyl methyl ether 9 1) to furnish the pure cycloadducts. 

Mixed carboxylic-carbonic anhydrides decompose in the presence of DMAP to give esters and carbon dioxide under mild conditions [Scheme 6.51). In the case of benzyl esters, the mixed carboxylic-carbonic anhydrides can be generated by reaction of the carboxylic acid with benzyl chloroformate in the presence of triethylamine (1.1 equiv) and DMAP (0.1 equiv) or more conveniently by reaction of the carboxylic acid with dibenzyl dicarbonate (dibenzyl pyrocarbo-nate) in THF or rm-butyl alcohol in the presence of DMAP (0.1 equiv). The reactions generally work well except for hindered carboxylic acid The method can also be used to make methyl, ethyl, rerr-butyl and allyl ester Carboxylic acids react vrith 2 equivalents of benzyl 2,2.2-trichloroacetimidate in the presence of a catalytic amount of boron trifluoride etherate to give the benzyl ester in modest to good yield. ... 

Here, the reaction between methyl iodide and the anion of 2-methyl-2-propanol (terr-butoxide) to form tm-butyl methyl ether is used to demonstrate the process in which a methyl group has been substituted for the proton originally on the oxygen of 2-methyl-2-propanol (tert-butanol) (Equation 8.21). The example of Equation 8.21 is also used to emphasize that the ether (rm-butyl methyl ether) cannot be prepared from the reaction between methoxide anion and 2-iodo-2-methylpropane (or indeed any 2-halo-2-methylpropane) because elinnnation would intrude (Equation 8.22). 

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