Dimethyl Sulfate → (2S,4S)-2-carbamoyl-4-(4-methoxybenzylthio)-1-methylpyrrolidine

10.86 ml of dimethyl sulfate were added to a solution of 30 g of (2S,4S)-2-carbamoyl-4-(4-methoxybenzylthio)pyrrolidine hydrochloride in a mixture of 36 ml of a 20% w/v aqueous solution of sodium hydroxide and 470 ml of dioxane, and the resulting mixture was stirred at a temperature of between 22° C. and 23° C. for 1 hour. At the end of this time, the reaction mixture was concentrated by evaporation under reduced pressure, and the resulting residue was extracted with 2 liters of ethyl acetate. The extract was washed with an aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate. The solution was then concentrated by evaporation under reduced pressure, until crystals emerged, and then 400 ml of diisopropyl ether were added to the mixture and the crystals which precipitated were collected by filtration, to give 23 g of the title compound as crystals, melting at 113°-114° C.

1. concentrationAt the end of this time, the reaction mixture was concentrated by evaporation under reduced pressure
2. extractionthe resulting residue was extracted with 2 liters of ethyl acetate
3. washThe extract was washed with an aqueous solution of sodium chloride
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationThe solution was then concentrated by evaporation under reduced pressure, until crystals
6. addition400 ml of diisopropyl ether were added to the mixture
7. customthe crystals which precipitated
8. filtrationwere collected by filtration

ORD record

ord-6658c46299a842bfba654f0a7532fd92

Source dataset

uspto-grants-1998_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05712267