반응 #487502

반응 방정식

2-methyl-1,3-cyclopentanedione

methyl iodide

KOH

dioxane

KOH

MeI

dioxane

KOH

MeI

dioxane

→

oil

수율 93.0%

2,2-Dimethyl-cyclopentane-1,3-dione

수율 93.0%

용매

water

water

water

반응 조건

후처리

1. 1
   기타Synthesized
2. 2
   온도was heated
3. 3
   온도at reflux
4. 4
   온도at reflux
5. 5
   온도heating
6. 6
   온도at reflux
7. 7
   workup.WAITAfter 4 hours
8. 8
   온도the mixture was cooled to room temperature
9. 9
   추출extracted with ether (1×100 mL, 3×75 mL)
10. 10
    기타The combined ether extracts were evaporated
11. 11
    기타placed in a 120° C.
12. 12
    기타(ca. 15 minutes)
13. 13
    온도The mixture was cooled to room temperature
14. 14
    workup.ADDITIONneutralized by addition of saturated NaHCO3 solution (150 mL)
15. 15
    추출the resulting mixture extracted with CH2Cl2 (4×75 mL)
16. 16
    건조The combined CH2Cl2 solution was dried (MgSO4)
17. 17
    여과filtered
18. 18
    기타evaporated

실험 절차

Synthesized according to Agosta and Smith, J. Org. Chem. 35: 3856 (1970) A mixture of 2-methyl-1,3-cyclopentanedione (10.025 g, 89.4 mmol, Aldrich), methyl iodide (6.0 mL, 96.4 mmol, Aldrich), and KOH (5.097 g, 90.8 mmol) in water (25 mL)/dioxane (75 mL) was heated at reflux. After 5 hours, a solution of KOH (2 g) and MeI (2.4 mL) in water (5 mL)/dioxane (15 mL) was added and after another 3 hours at reflux, the solution was stirred at room temperature overnight. A solution of KOH (2 g) and MeI (2.4 mL) in water (5 mL)/dioxane (15 mL) was added to the overnight reaction and heating at reflux. After 4 hours, the mixture was cooled to room temperature and extracted with ether (1×100 mL, 3×75 mL). The combined ether extracts were evaporated, the residue combined with 10% HCl (50 mL), and the resulting mixture placed in a 120° C. oil bath until it began boiling (ca. 15 minutes). The mixture was cooled to room temperature, neutralized by addition of saturated NaHCO3 solution (150 mL) and the resulting mixture extracted with CH2Cl2 (4×75 mL). The combined CH2Cl2 solution was dried (MgSO4), filtered and evaporated to leave a brown oil (10.474 g, 83 mmol, 93%) which was used directly in the next step.

출처