Reaktion #527847

Reaktionsgleichung

pyridine

3-(4,6-dichloro-2,3-dihydro-2,2-dimethylbenzofuran-3-on-7-yl)-1-methyl-6-trifluoromethyluracil

0-methylhydroxylamine hydrochloride

ethanol

→

3-(4,6-dichloro-2,3-dihydro-2,2-dimethyl-3-methoxyiminobenzofuran-7-yl)-1-methyl-6-trifluoromethyluracil

Ausbeute 21.2%

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeIn a flask were placed
2. 2
   TemperaturThis mixture was heated
3. 3
   Temperaturat reflux for five hours
4. 4
   Sonstigewas evaporated under reduced pressure
5. 5
   Sonstigeleaving a residue
6. 6
   Waschenthis solution was washed with water
7. 7
   ExtraktionThe aqueous washings were then extracted twice with ethyl acetate
8. 8
   TrocknenThe combined extracts and solution was dried over anhydrous magnesium sulfate
9. 9
   Filtrationfiltered
10. 10
    Sonstigethe solvent was evaporated from the filtrate under reduced pressure
11. 11
    Sonstigeleaving a light reddish, viscous oil as a residue
12. 12
    Wascheneluting with methylene chloride
13. 13
    Sonstigethe solvent evaporated under reduced pressure

Vorschrift

In a flask were placed 3.20 g (0.0076 mole) of 3-(4,6-dichloro-2,3-dihydro-2,2-dimethylbenzofuran-3-on-7-yl)-1-methyl-6-trifluoromethyluracil, 1,20 g (0.0144 mole) of 0-methylhydroxylamine hydrochloride, 4 mL of ethanol, and 4 mL of pyridine. This mixture was heated at reflux for five hours and then was evaporated under reduced pressure, leaving a residue. The residue was dissolved in ethyl acetate, and this solution was washed with water. The aqueous washings were then extracted twice with ethyl acetate, and these extracts were combined with the ethyl acetate solution of the product. The combined extracts and solution was dried over anhydrous magnesium sulfate, filtered, and the solvent was evaporated from the filtrate under reduced pressure, leaving a light reddish, viscous oil as a residue. This oil was passed through a column of silica gel, eluting with methylene chloride. Product-containing fractions were combined, and the solvent evaporated under reduced pressure, leaving 0.73 g of 3-(4,6-dichloro-2,3-dihydro-2,2-dimethyl-3-methoxyiminobenzofuran-7-yl)-1-methyl-6-trifluoromethyluracil (Compound 26) as an off-white, fluffy solid, m.p. 145°-149° C. The NMR and IR spectra were consistent with the proposed structure.

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