Reaktion #1675333

Reaktionsgleichung

oxygen

4,4'-pentamethylenebis[1-(2-hydroxyethyl)-2,5-dimethoxy-3,6-bis(methoxymethoxy)benzene]

hydrogen chloride

sodium hydrogen carbonate

→

5,5'-pentamethylenebis[2-(2-hydroxyethyl)-3,6-dimethoxy-1,4-benzoquinone]

Lösungsmittel

methanol

tetrahydrofuran

isopropanol

tetrahydrofuran isopropanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   EinengenThe reaction mixture was concentrated
3. 3
   Sonstigeto the residue obtained
4. 4
   Filtrationthe reaction mixture was filtered
5. 5
   Einengenconcentrated
6. 6
   Sonstigethe residue obtained
7. 7
   workup.ADDITIONwas treated by means of a preparative thin layer chromatography (silica gel plate
8. 8
   Sonstigeethyl acetate:benzene=1:1), then recrystallized from petroleum ether

Vorschrift

402 Milligrams of 4,4'-pentamethylenebis[1-(2-hydroxyethyl)-2,5-dimethoxy-3,6-bis(methoxymethoxy)benzene] was dissolved in a mixed solvent of 4 ml of tetrahydrofuran with 4 ml of isopropanol, under ice-cooling conditions, 0.8 ml of tetrahydrofuran-isopropanol (1:1) solution containing 20% of hydrogen chloride was added thereto. The reaction mixture was heated at 50° C. on a water bath for 5 hours with stirring. The reaction mixture was concentrated, and to the residue obtained was added 10 ml of methanol and a small amount of sodium hydrogen carbonate, then whole mixture was heated at 50 to 60° C., on a water bath and oxygen gas was blown into the reaction mixture for 5 hours. After the reaction was completed, the reaction mixture was filtered, and concentrated, the residue obtained was treated by means of a preparative thin layer chromatography (silica gel plate: 20×20 cm, thickness 2 mm, 2 plates were used, developing solvent: ethyl acetate:benzene=1:1), then recrystallized from petroleum ether to obtain 305 mg of 5,5'-pentamethylenebis[2-(2-hydroxyethyl)-3,6-dimethoxy-1,4-benzoquinone] was obtained. Yellow needles crystals.

Quelle