反应详情

1-Methyl-2-pyrrolidinone (10 mL) was added to mercaptoacetic acid dilithium salt monohydrate (from part (a) above, 1.21 g, 10 mmol) and the mixture was stirred for 10 minutes at room temperature. 3-Benzyl-7-(420 nitrophenylsulfonyl)-9-oxa-3,7-diazabicyclo[3.3.1]nonane (2 g, 5 mmol, see Example 2 above) was added and the mixture stirred at room temperature under nitrogen for 2.5 hours. Toluene (8 mL) and 2-propanol (15 mL) were added to the bright orange reaction solution. The internal temperature was adjusted to 40–45° C. A solution of hydrogen chloride in 2-propanol (10 mL, approx. 4M) was added dropwise whilst maintaining the above internal temperature range. Stirring was continued for 30 minutes in this temperature range. A white precipitate formed and the mixture was cooled slowly to room temperature with stirring. The mixture was stirred overnight and then cooled in an ice/water bath to 7° C. The precipitate was collected by filtration, washed with 2-propanol (2×5 mL) and sucked dry on the filter to give the title compound as a white powder (1.28 g, 88%).

1. stirringthe mixture stirred at room temperature under nitrogen for 2.5 hours
2. customwas adjusted to 40–45° C
3. temperaturewhilst maintaining the above internal temperature range
4. stirringStirring
5. waitwas continued for 30 minutes in this temperature range
6. customA white precipitate formed
7. temperaturethe mixture was cooled slowly to room temperature
8. stirringwith stirring
9. stirringThe mixture was stirred overnight
10. temperaturecooled in an ice/water bath to 7° C
11. filtrationThe precipitate was collected by filtration
12. washwashed with 2-propanol (2×5 mL)
13. customsucked dry on the
14. filtrationfilter