Dimethyl Sulfate → HCID 73074217, compound

Participants

Reaction Steps

A suspension of 6 (52 g, 0.16 mol) in tetrahydrofuran (THF, 150 mL) was stirred at room temperature for about 30 min and cooled to −10 to −15° C. A solution of potassium hexamethyldisilylamide (KHMDS, 40% solution in THF, 144 mL, 0.256 mol) was slowly added while controlling the temperature between −5 and −15° C. After 15 min, dimethyl sulfate (18.7 mL, 1.20 mol) was added dropwise to the reaction mixture while maintaining a temperature between −10 and 0° C., and the resulting reaction mixture was then stirred at this temperature for about 30 min. The reaction mixture was quenched by the addition of water (100 mL), followed by acetic acid (50 mL). The product was extracted with methyl tert-butyl ether (2×150 mL). The combined organic layer was washed with water (100 mL), brine (50 mL) and dried over anhydrous Na2SO4. Evaporation under reduced pressure gave compound 7 as an oil (54 g).

Provenance & Evidence