反应详情

温度

0 °C

tert-Butyl (3R,4R)-3-amino-4-(hydroxymethyl)-3-isothiazol-5-yl-pyrrolidine-1-carboxylate (148.10 g, 494.67 mmol) and tetrahydrofuran (1.48 L) are added together and the solution is cooled to 0° C. Benzoyl isothiocyanate (82.34 g, 504.56 mmol) is added over 5 minutes and the reaction mixture is stirred for 30 minutes at 0° C. and then warmed to room temperature over 1 hour. 1,1′-Carbonyldiimidazole (92.24 g, 568.87 mmol) is added and the reaction mixture is stirred at room temperature for 2 h. The mixture is heated to 65° C. and stirred for a further 12 hours. The reaction mixture is concentrated under reduced pressure and the oily residue is partitioned between water (1.5 L) and ethyl acetate (1.5 L). The pH is adjusted with citric acid 50% w/w aq. solution to 4.0 and the organic layer is separated. The aqueous layer is extracted with MTBE (2×500 mL), the organics are combined, dried over sodium sulfate, filtered, and evaporated under reduced pressure. The crude product is slurried in MTBE (740.50 mL) at 60° C. then at room temperature for 45 minutes. The solid is collected, washed with MTBE (4×150 mL), and dried under vacuum overnight to give the title compound as an off white solid (162.68 g, 74.0%). ES/MS (m/e): 445 (M+H), ee=99.5%.

1. temperaturewarmed to room temperature over 1 hour
2. stirringthe reaction mixture is stirred at room temperature for 2 h
3. temperatureThe mixture is heated to 65° C.
4. stirringstirred for a further 12 hours
5. concentrationThe reaction mixture is concentrated under reduced pressure
6. customthe oily residue is partitioned between water (1.5 L) and ethyl acetate (1.5 L)
7. customthe organic layer is separated
8. extractionThe aqueous layer is extracted with MTBE (2×500 mL)
9. dry with materialdried over sodium sulfate
10. filtrationfiltered
11. customevaporated under reduced pressure
12. customis slurried in MTBE (740.50 mL) at 60° C.
13. waitat room temperature for 45 minutes
14. customThe solid is collected
15. washwashed with MTBE (4×150 mL)
16. customdried under vacuum overnight