Glycol sulfates, cyclic glycols

Cyclic sulfites and cyclic sulfates of ethanediol undergo hydrolysis with acids to furnish glycol. The substituted cyclic sulfate, such as tetramethyl-1,3,2-dioxathiolane 2-dioxide, may undergo a pinacol type of rearrangement under acidic conditions to furnish pinacolone in good yield (74JOC3415). The mechanistic pathway is rationalized in Scheme 17. 

Ruthenium trichloride sodium periodate Cyclic glycol sulfates from glycols... 

Regio- and stereo-specific nucleophilic ring opening of cyclic glycol sulfates C... 

To 5.69 g of this acetal in 410 ml of t-butanol and 11 ml of water was added a mixture of 5.80 g of potassium carbonate, 22,8 g of sodium periodate, and 270 mg of potassium permanganate in 1230 ml of water. The reaction mixture was stirred at 20-25°C for 20 hours and concentrated in vacuo to remove t-butanol. Ethylene glycole (0.5 ml) was added and reaction mixture extracted with 1 1 ether-benzene to remove neutral material. The aqueous layer acidified with solid sodium dihydrogen phosphate and extracted 4 times with 1 1 ethyl acetate-benzene. The organic layer was dried over sodium sulfate and evaporated to dryness in vacuo affording (+/-)-3-acetyl-2a-(2-carboxyethyl)-5-oxo-ip-cyclopentaneheptanoic acid methyl ester, 5-cyclic ethylene acetal as a mixture of the 3a and 3p isomers. 

The first cyclic acetals of this type were prepared by Wurtz 14 ), who showed that ethylene glycol and acetaldehyde react when heated together and that one mole of water is lost. Mineral acids, zinc chloride, and copper sulfate greatly accelerate the reaction. 

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