반응 #461584

ord-25d9e7780cf346639ca19a894be80314

반응 조건

온도
0°CELSIUS
상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    기타was kept below 5° C
  2. 2
    기타to come to room temperature
  3. 3
    workup.WAITFinally, it was left at room temperature for 14 h
  4. 4
    workup.ADDITIONstrongly mixed
  5. 5
    여과The resulting suspension was filtered by suction
  6. 6
    세척the cake was washed three times with 250 ml of 95% ethanol
  7. 7
    workup.ADDITIONTo the combined filtrates and washings 1 l of ether was added
  8. 8
    workup.WAITthe solution was kept at 0° C. for 24 h
  9. 9
    기타The desired product crystallized as white cubes, while the yellowish needles that
  10. 10
    기타It could be separated
  11. 11
    workup.STIRRINGby stirring up the whole mixture
  12. 12
    기타decanting the liquid with the floating needles while the product
  13. 13
    workup.ADDITIONBy addition of 1 l of ether to the mother liquid a second crop
  14. 14
    기타could be isolated
  15. 15
    기타The product was recrystallized two times from water/ethanol/ether

실험 절차

Glucosamine hydrochloride (0.1 mol; 21.56 g) and sodium nitrite (0.2 g) as inhibitor were dissolved under nitrogen atmosphere in 100 ml of a 0.3 M potassium carbonate solution, and the mixture was cooled to 0° C. Under vigorous stirring, acryloyl chloride (0.2 mol; 18.1 g) was added while the temperature was kept below 5° C. Stirring was continued for 3 h at 0°-5° C. and further 2 h while the mixture was allowed to come to room temperature. Finally, it was left at room temperature for 14 h. The solution was poured into 1 l of dry ethanol and strongly mixed. The resulting suspension was filtered by suction, and the cake was washed three times with 250 ml of 95% ethanol. To the combined filtrates and washings 1 l of ether was added and the solution was kept at 0° C. for 24 h. The desired product crystallized as white cubes, while the yellowish needles that might appear were a by-product. It could be separated by stirring up the whole mixture and decanting the liquid with the floating needles while the product remained on the ground of the reaction flask. By addition of 1 l of ether to the mother liquid a second crop could be isolated. The product was recrystallized two times from water/ethanol/ether. Yield 8.1-10.5 g (35-45%), m.p.:124°-125° C.

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US05480790uspto-grants-1996_01