Reaktion #220022

Reaktionsgleichung

compound

3-Formyl-2-hydroxy-5-trifluoromethylpyridine

sodium formate

hydroxylamine hydrochloride

formic acid

→

desired product

3-Cyano-2-hydroxy-5-trifluoromethylpyridine

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated
2. 2
   Temperaturto reflux overnight
3. 3
   TemperaturThe reaction mixture was cooled
4. 4
   workup.WAITto stand at room temperature for 7 d
5. 5
   Extraktionextracted with three portions of ethyl acetate
6. 6
   WaschenThe combined organic layers were washed sequentially with two portions of water, saturated aqueous sodium bicarbonate solution and brine
7. 7
   Trocknendried over sodium sulfate
8. 8
   Einengenconcentrated in vacuo

Vorschrift

A mixture of the compound from Step B above (18 g, 95 mmol), sodium formate (7.1 g, 110 mmol), hydroxylamine hydrochloride (7.3 g, 110 mmol), and formic acid (150 mL) was stirred at room temperature for 2 h and then heated to reflux overnight. The reaction mixture was cooled, allowed to stand at room temperature for 7 d, poured into water and extracted with three portions of ethyl acetate. The combined organic layers were washed sequentially with two portions of water, saturated aqueous sodium bicarbonate solution and brine, dried over sodium sulfate and concentrated in vacuo to yield the desired product as a brown powder. 1H NMR (400 MHz, CD3OD) δ 8.37 (d, J=2.7 Hz, 1H), 8.19 (q, J=0.7 Hz, 0.3 Hz, 1H).

Quelle