Reaktion #64051

Reaktionsgleichung

2-butyryl-3-hydroxy-5-mesitylcyclohex-2-en-1-one

dichloromethyl methyl ether

→

2-butyryl-3-hydroxy-5-(3-formyl-2,4,6-trimethylphenyl)cyclohex-2-en-1-one

Ausbeute 26.7%

Lösungsmittel

dichloroethane

dichloroethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added dropwise over a 25 minute period
2. 2
   workup.ADDITIONAfter the addition
3. 3
   workup.STIRRINGthe mixture was stirred for 5 minutes at 0° C., for 30 minutes at room temperature and for 2 hours
4. 4
   Temperaturunder reflux
5. 5
   SonstigeThe cooled reaction mixture
6. 6
   workup.ADDITIONwas poured into a separatory funnel
7. 7
   workup.ADDITIONcontaining
8. 8
   Sonstigecrushed ice
9. 9
   workup.STIRRINGwas shaken thoroughly
10. 10
    SonstigeThe organic layer was separated
11. 11
    Extraktionthe aqueous solution was extracted with methylene chloride
12. 12
    WaschenThe combined organic solution was washed with water
13. 13
    Trocknendried over anhydrous sodium sulfate
14. 14
    Sonstigeevaporated to dryness
15. 15
    Sonstigeto give a crude brown oil (0.70 g)
16. 16
    SonstigePurification by column chromatography over silica gel (eluant dichloromethane)

Vorschrift

To a solution of 2-butyryl-3-hydroxy-5-mesitylcyclohex-2-en-1-one (1.20 g) in dichloroethane (20 ml) at 0° C. was added titanium tetrachloride (300 g) over a period of 3 minutes. While the solution was stirred and cooled dichloromethyl methyl ether (0.46 g) in dichloroethane(20 ml) was added dropwise over a 25 minute period. After the addition was complete, the mixture was stirred for 5 minutes at 0° C., for 30 minutes at room temperature and for 2 hours under reflux. The cooled reaction mixture was poured into a separatory funnel containing crushed ice and was shaken thoroughly. The organic layer was separated, and the aqueous solution was extracted with methylene chloride. The combined organic solution was washed with water, dried over anhydrous sodium sulfate and evaporated to dryness to give a crude brown oil (0.70 g). Purification by column chromatography over silica gel (eluant dichloromethane) gave 2-butyryl-3-hydroxy-5-(3-formyl-2,4,6-trimethylphenyl)cyclohex-2-en-1-one (0.35 g) as a pale yellow oil. Proton nuclear magnetic resonance spectrum (CDCl3 ; δ in ppm): 1.0 (3H, t); 1.68 (2H, m); 2.43 (3H, s); 2.48 (3H, s); 2.61 (3H, s); 2.65-4.20 (7H, m); 6.94 (1H, s); 10.54 (1H, s); 18.33 (1H, s).

Quelle