Tert-Butyl hydrogen sulfate

Example 2.5 tert-Butyl hydrogen sulfate is required as an intermediate in a reaction sequence. This can be produced by the reaction between isobutylene and moderately concentrated sulfuric acid ... 

Series reactions occur in which the tert-butyl hydrogen sulfate reacts to unwanted tert-butyl alcohol ... 

Sulfuric acid is about one thousand times more reactive with isobutylene than with the 1- and 2-butenes, and is thereby very useful in separating isobutylene as tert-butyl alcohol from the other butenes. The reaction is simply carried out by bubbling or stirring the butylenes into 45—60% H2S04. This results in the formation of tert-butyl hydrogen sulfate. Dilution with water followed by heat hydrolyzes the sulfate to form butyl alcohol and sulfuric acid. The Markovnikov addition implies that isobutyl alcohol is not formed. The hydration of butylenes is most important for isobutylene, either directly or via the butyl hydrogen sulfate. 

Hg [212], is prepared from tert-butyl hydrogen sulfate and 27% hydrogen peroxide [212] and is commercially available as a 70 or 90% solution containing water and tert-butyl alcohol. Anhydrous rert-butyl hydroperoxide is obtained from the 70% aqueous solution by azeotropic distillation with toluene [213]. Anhydrous, as well as highly concentrated, tert-bvXy hydroperoxide must be handled with utmost care, because it may decompose violently in the presence of strong acids and some transition metals, especially manganese, iron, and cobalt [213, 214],... 

Step 3 in Figure 5 6 shows water as the base which ab stracts a proton from the car bocation Other Bronsted bases present in the reaction mixture that can function in the same way include tert butyl alcohol and hydrogen sulfate ion... 

Although 2 methylpropene undergoes acid catalyzed hydration m dilute sulfuric acid to form tert butyl alcohol (Section 6 10) a different reaction occurs m more concentrated solutions of sulfuric acid Rather than form the expected alkyl hydrogen sulfate (see Sec tion 6 9) 2 methylpropene is converted to a mixture of two isomeric C Hig alkenes... 

The Intermediate In this synthesis of disparlure, (Z)-2-tridecenol, Is obtained by hydrogenation of 2-trldecynol In the presence of a palladium catalyst poisoned with barium sulfate and quinoline. Oxidation of (Z)-2-tridecenol with tert-butyl hydroperoxlde/tItanium tetralsopropoxlde/D (-)-diethyl tartrate gives (2R, 3S)-epoxytrldecanol In enantiomeric excess reported to be as much as 98 percent after recrystalllzatlon. 

A solution of hydrogen peroxide in fer/-butyl alcohol is prepared by adding 400 mL of pure tert-butyl alcohol (free of isobutylene) to 100 mL of 30% hydrogen peroxide. The solution is treated with small portions of anhydrous sodium sulfate until two layers separate. The alcohol layer is removed and dried with anhydrous sodium sulfate and finally with anhydrous calcium sulfate (Drierite). The solution contains 6.3% of hydrogen peroxide in ferf-butyl alcohol. 

Hydrogen peroxide and ferrous sulfate react to produce hydroxyl radical (HO-), as reported in 1894 by English chemist H. J. H. Fenton. When tert-butyl alcohol is treated with HO- generated this way, it affords a crystalline reaction product X, mp 92 °C, which has these spectral properties ... 

Typical procedure. tert-Butyl 2-isocyano-4-methyl pentanoate 1554 [1182] N-Formyl-leucine tert-butyl ester 1553 (5.00 g, 23.2 mmol) and triethylamine (7.13 g, 69.7 mmol) were dissolved in dichloromethane (36 mL) and the solution was cooled to 0 °C. At this temperature, a solution of triphosgene (2.30 g, 7.74 mmol) in dichloromethane (25 mL) was added dropwise. The mixture was stirred for 2 h at room temperature, water (5 mL) was then poured into it, and the phases were separated. The organic layer was washed with 5% aq. sodium hydrogen carbonate solution, dried over sodium sulfate, and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate to furnish tert-butyl 2-isocyano-4-methyl pentanoate 1554 (4.29 g, 94%) as a colorless oil. 

The presence of thallium(0) led to an increase in activity and selectivity of metallic palladium catalysts supported on silica in aldose oxidation reactions. However, silica-supported thallium(0) had no activity by itself (entry 3). ° Similarly, the bimetallic catalyst platinum-thallium/ZSM-5, prepared by impregnation of thallium sulfate and chloroplatinic acid on Zeolite Socony Mobil-5 (ZSM-5), showed greater selectivity in propane aromatisation and almost the same catalytic activity as monometallic thallium/ZSM-5 (entry 4). Similar comparison of vanadium-caesium-copper and vanadium-caesium-copper-thallium catalysts supported on TiOa.SiC demonstrated that addition of thallium improved the catalytic activity in partial oxidation of p-tert-butyltoluene to p-tert-butyl-benzaldehyde (entry The application of solid-supported thallium-based catalysts in different processes includes (a) iron-thallium catalysts in carbon monoxide hydrogenations to form hydrocarbons and alcohols, and catalytic reforming of... 

The following commercially available dialkyl peroxides are produced according to equations 24—27 di-Z fZ-butyl peroxide from hydrogen peroxide and sulfated tert-huty alcohol or isobutylene dicumyl peroxide from a-cumyl hydroperoxide and cumyl alcohol, cumyl chloride, and/or a-methylstyrene m- and -di(2-/ f2 -butylperoxyisopropyl)ben2ene [2781-00-2] from tert-huty hydroperoxide [75-91-2] and m- and -di(2-hydroxyisopropyl)ben2ene ... 

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