反应详情

温度

50 °C

To 240 ml of a chloroform solution containing 30 g of (4R,5R)-1,3-dibenzyl-2-oxo-5-(mercaptomethyl)imidazolidin-4-carboxylic acid, 22.7 g of pyridine and 2.6 ml of trifluoroacetic acid was added dropwise 60 ml of a chloroform solution containing 17.4 g of dicyclohexylcarbodiimide at 5° C. over 30 minutes. After the solution was refluxed for 5 hours, it was concentrated under reduced pressure. The concentrate was dissolved in ethyl acetate and concentrated, and after the procedure was repeated, 300 ml of ethyl acetate was added to the residue, and the mixture was stirred at 50° C. for 30 minutes. After cooling to 25° C., insoluble materials were filtered off. After the filtrate was concentrated, 85 ml of methanol was added to the concentrate and the mixture was dissolved under heating. After cooling the solution, precipitated crystal was collected by filtration, and washed with cold methanol. Precipitated crystal was dried by blowing air at 50° C. to give 21.3 g of (3aS,6aR)-1,3-dibenzyl-hexahydro-4H-thieno[3,4-d]imidazol-2,4-dione as colorless crystal.

1. temperatureAfter the solution was refluxed for 5 hours
2. concentrationit was concentrated under reduced pressure
3. dissolutionThe concentrate was dissolved in ethyl acetate
4. concentrationconcentrated
5. addition300 ml of ethyl acetate was added to the residue
6. temperatureAfter cooling to 25° C.
7. filtrationinsoluble materials were filtered off
8. concentrationAfter the filtrate was concentrated
9. addition85 ml of methanol was added to the
10. concentrationconcentrate
11. dissolutionthe mixture was dissolved
12. temperatureunder heating
13. temperatureAfter cooling the solution
14. customprecipitated crystal
15. filtrationwas collected by filtration
16. washwashed with cold methanol
17. customPrecipitated crystal
18. customwas dried
19. customat 50° C.