Reaktion #8738

Reaktionsgleichung

(3-bromothiophen-2-yl)-(3-methoxyphenyl)methanone oxime

KOH

2-ethoxyethanol

→

title compound

Ausbeute 68.0%

3-(3-methoxyphenyl)thieno[2,3-d]isoxazole

Ausbeute 68.0%

Lösungsmittel

hexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturReflux
2. 2
   TemperaturHeat the reacton for an additional four hours
3. 3
   ExtraktionAdd water and extract the organics into ether
4. 4
   WaschenWash the ether phase with water
5. 5
   Trocknendry (MgSO4)
6. 6
   Filtrationfilter
7. 7
   Einengenconcentrate
8. 8
   Sonstigeto yield an oil
9. 9
   SonstigePurify the oil by column (alumina) chromatography
10. 10
    Waschenelute with 15% ether in hexane
11. 11
    Sonstigeto obtain white crystals
12. 12
    SonstigeRecrystallize the crystals from ether

Vorschrift

Reflux a mixture of (3-bromothiophen-2-yl)-(3-methoxyphenyl)methanone oxime (10 g, 0.032 mol), KOH (3.6 g, 0.064 mol dissolved in 10 mL water) and 2-ethoxyethanol (40 mL) under nitrogen for one hour at 105–110° C. Add copper chloride (0.16 g, 0.0016 mol) whereupon the reaction mixture becomes dark brown in color. Heat the reacton for an additional four hours. TLC shows that the reaction is complete. Add water and extract the organics into ether. Wash the ether phase with water, dry (MgSO4), filter and concentrate to yield an oil. Purify the oil by column (alumina) chromatography, and elute with 15% ether in hexane to obtain white crystals. Recrystallize the crystals from ether:hexane to yield the title compound (5 g, 68% Yield), m.p. 51–52° C.

Quelle