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-huty alcohol from the other butenes. The reaction is simply carried out by bubbling or stirring the butylenes into 45—60% H2SO4. This results in the formation of tert-huty hydrogen sulfate. Dilution with water followed by heat hydrolyzes the sulfate to form tert-huty alcohol and sulfuric acid. The Markovnikov addition implies that isobutyl alcohol is not formed. The hydration of butylenes is most important for isobutylene, either directiy or via the butyl hydrogen sulfate. 

A typical feed to a commercial process is a refinery stream or a steam cracker B—B stream (a stream from which butadiene has been removed by extraction and isobutylene by chemical reaction). The B—B stream is a mixture of 1-butene, 2-butene, butane, and isobutane. This feed is extracted with 75—85% sulfuric acid at 35—50°C to yield butyl hydrogen sulfate. This ester is diluted with water and stripped with steam to yield the alcohol. Both 1-butene and 2-butene give j -butyl alcohol. The sulfuric acid is generally concentrated and recycled (109) (see Butyl alcohols). 

The sulfation reaction occurs in the liquid phase at approximately 35 °C. An 85 wt% alcohol yield could be realized. The reaction is similar to the sulfation of ethylene or propylene and results in a mixture of sec-butyl hydrogen sulfate and di-sec-butyl sulfate. The mixture is further hydrolyzed to sec-butanol and sulfuric acid ... 

Acid Sulfates. Pasteur 6 and also Le Bel4 fractionated the cinchonine salts of the mixture of amyl hydrogen sulfates derived from fusel oil and effected a partial separation of the structurally isomeric alcohols. Krtiger 41 failed to resolve the alkaloid salts of the hydrogen sulfate of ethyl-n-propylcarbinol but Meth,42 after failures in other instances, finally effected a partial resolution of a-butyl hydrogen sulfate as the brucine salt. The method has proved to be impracticable for most alcohols 48 because the majority of alkyl hydrogen sulfates are unstable and inconvenient to handle. 

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],... 

Op 1.3872 at 20° stable in the presence of coned HCl strong bases can be prepd from t-butyl alcohol H2O2 t-butyl hydrogen sulfate t-butyl hydroperoxide and by reaction, of t-butyl alcohol or isobutylene, sulfuric acid H2O2 (Ref 2). The latter reaction... 

ETHERS Antimony(V) fluoride. Hexamethylphosphorus triamide. Tetra-n-butyl hydrogen sulfate. Thallium(I) ethoxide. Triphenylphosphine-Diethyl azodicarboxylate. ETHYL KETONES Sodium tetracarbonylferratefll). 

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