Reaktion #623782

Reaktionsgleichung

sodium hydroxide

5-chlorofuran-2-carboxaldehyde

ammonium hydroxide

→

white solid

Ausbeute 95.0%

5-Chlorofuran-2-carboxylic acid

Ausbeute 95.0%

Lösungsmittel

water

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe resulting mixture was stirred at ambient temperature for 30 min
2. 2
   FiltrationThe reaction mixture was filtered
3. 3
   Waschenthe filtrate was washed with ether (100 mL)
4. 4
   workup.ADDITIONmade acidic (˜pH 3) by the addition of cold 20% sulfuric acid
5. 5
   ExtraktionThe resulting mixture was extracted with ethyl acetate (3×100 mL)
6. 6
   WaschenThe extracts were washed with saturated aqueous sodium chloride solution (100 mL)
7. 7
   Trocknendried (anhydrous sodium sulfate)
8. 8
   Einengenconcentrated under vacuum

Vorschrift

Aqueous sodium hydroxide (80 mL of 10%) was added to a solution of silver nitrate (8.0 g, 47 mmol) in water (20 mL). This suspension was stirred and slowly treated with 30% aqueous ammonium hydroxide until it became clear. A solution of 5-chlorofuran-2-carboxaldehyde (3.0 g, 23 mmol) (Aldrich Chemical) in methanol (5 mL) was added, and the resulting mixture was stirred at ambient temperature for 30 min. The reaction mixture was filtered, and the filtrate was washed with ether (100 mL). The aqueous filtrate was then made acidic (˜pH 3) by the addition of cold 20% sulfuric acid. The resulting mixture was extracted with ethyl acetate (3×100 mL). The extracts were washed with saturated aqueous sodium chloride solution (100 mL), dried (anhydrous sodium sulfate) and concentrated under vacuum to give 3.2 g (95% yield) of white solid (mp 178-179° C.). This reaction was easily scalable and was run multiple times at >10 g scale.

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