반응 #335034

반응 방정식

2-hydroxyacetophenon

acetone

pyrrolidine

→

3,4-dihydro-2,2-dimethyl-2H-benzo[b]pyran-4-one

수율 21.6%

용매

toluene

반응 조건

후처리

1. 1
   온도heated
2. 2
   온도refluxed
3. 3
   기타Twenty hours
4. 4
   기타was returned to ambient temperature
5. 5
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure, to which
6. 6
   workup.ADDITIONwas added 100 ml of 1N hydrogen chloride
7. 7
   추출The extraction
8. 8
   세척by washing in water
9. 9
   건조drying over anhydrous magnesium sulfate
10. 10
    여과filtering off
11. 11
    기타condensation of the filtered solution
12. 12
    기타The residue was purified on a silica gel column the fraction
13. 13
    workup.ADDITIONcontaining the purified product
14. 14
    workup.ADDITIONwere mixed together
15. 15
    workup.DISTILLATIONthe solvent therein was distilled off under reduced pressure

실험 절차

Twenty five grams (25 g) of 2-hydroxyacetophenon, 10.7 g of acetone, and 5.5 g of pyrrolidine were added to 50 ml of toluene, and heated and refluxed. Twenty hours later, the temperature was returned to ambient temperature and the solvent was distilled off under reduced pressure, to which was added 100 ml of 1N hydrogen chloride. The extraction was carried out with 50 ml×3 of chloroform, followed by washing in water, drying over anhydrous magnesium sulfate, filtering off and condensation of the filtered solution. The residue was purified on a silica gel column the fraction containing the purified product were mixed together and the solvent therein was distilled off under reduced pressure to obtain 7 g of 3,4-dihydro-2,2-dimethyl-2H-benzo[b]pyran-4-one.

출처