Reaktion #1675338

Reaktionsgleichung

oxygen

hydrogen chloride

sodium hydrogen carbonate

2-[2,5-dimethoxy-3,6-bis(methoxymethoxy)phenyl]ethyl 3-[2,5-dimethoxy-3,6bis(methoxymethoxy)phenyl]propyl ether

→

2-(3,6-dimethoxy1,4-benzoquinon-2-yl)ethyl 3-(3,6-dimethoxy-1,4-benzoquinon2-yl)propyl ether

Lösungsmittel

dichloromethane

tetrahydrofuran

isopropanol

methanol

tetrahydrofuran

isopropanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared
2. 2
   EinengenThe reaction mixture was concentrated
3. 3
   workup.ADDITIONbenzene was added
4. 4
   workup.ADDITIONthen further treated under reduced pressure
5. 5
   Einengento concentrated
6. 6
   SonstigeThe residue obtained
7. 7
   workup.DISSOLUTIONThe precipitated crystals were dissolved
8. 8
   Filtrationfiltered
9. 9
   EinengenThe filtrate was concentrated
10. 10
    Sonstigethe residue obtained
11. 11
    Sonstigewas purified by means of a silica gel column chromatography
12. 12
    Sonstige10% ethyl acetate-dichloromethane solution, adsorbent: "Wakogel C-200", to obtain a crude product
13. 13
    Sonstigerecrystallized from ethanol

Vorschrift

484 Milligrams of 2-[2,5-dimethoxy-3,6-bis(methoxymethoxy)phenyl]ethyl 3-[2,5-dimethoxy-3,6bis(methoxymethoxy)phenyl]propyl ether was dissolved in a mixed solvent of 5 ml of tetrahydrofuran with 5 ml of isopropanol, to this solution was added 1.0 ml of solution prepared by dissolving 10% (by weight) of hydrogen chloride in a mixture of tetrahydrofuran with isopropanol (1:1), and the whole mixture was stirred at room temperature for 14 hours. The reaction mixture was concentrated, and benzene was added then further treated under reduced pressure to concentrated. The residue obtained was dissolved in 10 ml of methanol, and a catalytical amount of sodium hydrogen carbonate was added thereto and oxygen gas was blown thereinto. The precipitated crystals were dissolved by adding dichloromethane and filtered. The filtrate was concentrated and the residue obtained was purified by means of a silica gel column chromatography, (diameter 2 cm×length 5 cm, developping solvent: 10% ethyl acetate-dichloromethane solution, adsorbent: "Wakogel C-200", to obtain a crude product, then recrystallized from ethanol to obtain 243 mg of 2-(3,6-dimethoxy1,4-benzoquinon-2-yl)ethyl 3-(3,6-dimethoxy-1,4-benzoquinon2-yl)propyl ether. Yellow needles crystals.

Quelle