Methyl fcrf-butyl ether

Figure 35 Lipase-catalyzed enantioselective acetylation of racemic 2-hydroxy acids 65 to their 2-acetoxy acids 66 using vinyl acetate as acyl donor in methyl fcrf-butyl ether as organic solvent.80...

Although methyl fcrf-butyl ether is still used in some states, the use of ethanol is much more common. There are several reasons for the preference for ethanol. Eirst, ethanol is cheaper than MTBE because of special tax breaks and subsidies that have been granted to producers of ethanol formed by fermentation. Second,... 

In some areas of the country, manufacturers are required from November to February to control the amounts of carbon monoxide produced when the gasoline burns. To do this, they add oxygenates, such as ethanol or methyl fcrf-butyl ether (MTBE), to the gasoline. You should try to observe the presence of these oxygenates, which may be observed in gasolines produced in carbon monoxide-containment areas. Because MTBE has been banned or partially baimed in most states (see previous essay), it is unlikely that you will observe MTBE. 

This test method covers the determination of methanol, ethanol, fcrf-butanol, methyl fcrf-butyl ether (MTBE), ethyl fcrf-butyl ether (ETBE), fcrf-amyl methyl ether (TAME), and diisopropyl ether (DIPE) in gasoline by infrared spectroscopy. The test method is suitable for determining methanol from 0.1 to 6 mass %, ethanol from 0.1 to 11 mass %, ferf-butanol from 0.1 to 14 mass %, and DIPE, MTBE, ETBE and TAME from 0.1 to 20 mass %. 

Azobisisobutyronitrile Cyclohexyl Methanesulfonyl Methanesulfonyl chloride Methyl fcrf-butyl ether t-Butyldiphenylsilyl t-Butyldiphenylsilyl chloride Trityl (triphenylmethyl) Tosyl... 

With potassium /m-butoxide in tetrahydrofuran, the dibromodihydro-3//-l-benzazepines 7 (R1 = H, F, Cl) undergo syn dehydrobromination to synthetically useful alkenyl bromides, e.g. 8 (R1 = Cl), accompanied by small amounts of debrominated materials, e.g, 9 (R1 = Cl), and the 3-fcrf-butyl ethers, e.g. 10b(R1 = Cl, R2 = -Bu).78 In contrast, with sodium hydroxide, or with sodium methoxide in dioxane/methanol, the yields of bromo compounds 8 decrease, and significant amounts of the methyl ethers, e.g. 10a (R1 = Cl R2 = Me), arc produced. A mechanistic rationale for these reactions has been offered. 

Steffan RJ, K McClay, S Vainberg, CW Condee, D Zhang (1997) Biodegradation of the gasoline oxygenates methyl ferf-butyl ether, ethyl fcrf-butyl ether, and amyl tcrt-butyl ether by propane-oxidizing bacteria. Appl Environ Microbiol 63 4216-4222. 

Compare, for example, these typical conditions used to make a methyl ether and a tert-butyl ether. The methyl ether is made, as you saw on p. 340, using methyl iodide in an 8 2 reaction. It needs a good nucleophile, so the alcohol is deprotonated to make an alkoxide with sodium hydride in DMF, which, as you saw on p. 345, is a good solvent for 8 2 reactions. The fert-butyl ether on the other hand is made simply by stirring the alcohol with fcrf-butanol and a little acid. No base is needed, and the reaction proceeds rapidly to give the fcrf-butyl ether. 

Under suitable conditions, alcohols can be added to the carbon-carbon double bond of an alkene to give an ether. The usefulness of this method of ether synthesis is limited to the interaction of alkenes that form stable carbocations and methanol or primary alcohols. An example is the commercial synthesis of fcrf-butyl methyl ether (MTBE). 2-Methylpropene and methanol are passed over an acid catalyst to give the ether. 

Acid-catalyzed addition of alcohols to alkenes is sometimes used. Billions of pounds of fcrf-butyl methyl ether (MTBE) have been prepared by the reaction ... 

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