Alkyl hydrogen sulfates, alcohols from

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. 

Ritter9,17 has expressed the view that the reactions involve the formation of a carbonium ion from the alcohol or alkene which subsequently A-alkylates the nitrile. The intermediate product was thought to be the imidol hydrogen sulfate (25) from which the hydrogen sulfate residue is displaced nucleophilically by the electron-rich group Y. 

The addition of H2SO1, changes the alkene precursor into alkyl hydrogen sulfate, which is an intermediate in this reaction. This intermediate is hydrated with water which yields an alcohol. From this, the products of precursors (a) and (b) can be obtained by hydration in an acid medium. 

Mannitol hexanitrate is obtained by nitration of mannitol with mixed nitric and sulfuric acids. Similarly, nitration of sorbitol using mixed acid produces the hexanitrate when the reaction is conducted at 0—3°C and at —10 to —75°C, the main product is sorbitol pentanitrate (117). Xylitol, ribitol, and L-arabinitol are converted to the pentanitrates by fuming nitric acid and acetic anhydride (118). Phosphate esters of sugar alcohols are obtained by the action of phosphorus oxychloride (119) and by alcoholysis of organic phosphates (120). The 1,6-dibenzene sulfonate of D-mannitol is obtained by the action of benzene sulfonyl chloride in pyridine at 0°C (121). To obtain 1,6-dimethanesulfonyl-D-mannitol free from anhydrides and other by-products, after similar sulfonation with methane sulfonyl chloride and pyridine the remaining hydroxyl groups are acetylated with acetic anhydride and the insoluble acetyl derivative is separated, followed by deacetylation with hydrogen chloride in methanol (122). Alkyl sulfate esters of polyhydric alcohols result from the action of sulfur trioxide—trialkyl phosphates as in the reaction of sorbitol at 34—40°C with sulfur trioxide—triethyl phosphate to form sorbitol hexa(ethylsulfate) (123). 

By hydrogenation of a-methyl-a-cyanotetrahydrofuran with Raney nickel as catalyst, a-methyl-a-tetrahydrofurfuryl amine is obtained (BP 48°C/12 mm Hg) which is alkylated by dimethyl sulfate to give a-methyl-a-tetrahydrofurfurylmethylamine (BP 70°C/40 mm Hg). The amine is then reacted with 4-chloro-3-sulfamyl benzene sulfochloride in the presence of an acid acceptor. The mixture is stirred overnight, the solvent (acetone or pyridine) is driven off under vacuum and the residue is recrystallized from alcohol. 

Ethylenimine is conveniently prepared from ethanolamine by heating the inner salt of the sulfate ester with aqueous alkali (37%). The method has been applied to other /3-amino alcohols to form the C-alkyl homologs of ethylenimine in which one to three of the four hydrogens may be substituted. The general procedure is illustrated by the synthesis of 2,2-dim ethyl ethylenimine (51%). The N-alkyl analogs can be made by treating the N-alkylethanolamine hydrochlorides with chlorosulfonic acid followed by the action of base on the intermediate sulfuric acid esters, as in the preparation of N-ethylethylenimine (70%). ... 

O-Alkylation is most pronounced when the enolate is least solvated. When the potassium salt of ethyl acetoacetate is treated with ethyl sulfate in the polar aprotic solvent HMPA, the major product (83%) results from O-alkylation. In THF, where ion clustering occurs, all of the product is C-alkylated. In r-butyl alcohol, where the acetoacetate anion is hydrogen bonded by solvent, again only C-alkylation is observed. 

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