Reaktion #720893

Reaktionsgleichung

phosphorus oxychloride

(S)-7-hydroxy-2-methyl-2-trifluoromethyl-2,3-dihydro-1H-imidazo[1,2-a]pyrimidin-5-one

sodium hydroxide

→

(S)-7-chloro-2-methyl-2-trifluoromethyl-2,3-dihydro-1H-imidazo[1,2-a]pyrimidin-5-one

Ausbeute 53.0%

Lösungsmittel

ethyl acetate

1,2-dichloroethane

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling
2. 2
   Sonstigethe reaction mixture is evaporated to dryness under vacuum
3. 3
   SonstigeThe residue obtained
4. 4
   Sonstigeobtained, to pH=6-7
5. 5
   SonstigeThe organic phase is then separated out
6. 6
   Trocknendried over magnesium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated under reduced pressure

Vorschrift

41.60 mL (446.50 mmol) of phosphorus oxychloride are added, at room temperature and under an argon atmosphere, to a suspension of 35 g (148.80 mmol) of (S)-7-hydroxy-2-methyl-2-trifluoromethyl-2,3-dihydro-1H-imidazo[1,2-a]pyrimidin-5-one in 350 mL of 1,2-dichloroethane. The resulting mixture is then heated at 70° C. for 4 hours. After cooling, the reaction mixture is evaporated to dryness under vacuum. The residue obtained is taken up in 35 mL of cold water and 500 mL of ethyl acetate. 32% sodium hydroxide is added to the mixture obtained, to pH=6-7. The organic phase is then separated out and then dried over magnesium sulfate, filtered and concentrated under reduced pressure to give 20 g of (S)-7-chloro-2-methyl-2-trifluoromethyl-2,3-dihydro-1H-imidazo[1,2-a]pyrimidin-5-one, the characteristics of which are as follows:

Quelle