Reaktion #65739

Reaktionsgleichung

p-hydroxyphenylglycine

triethylamine

S-t-butoxycarbonyl-4,6-dimethyl-2-mercaptopyrimidine

→

N-Boc-p-hydroxyphenylglycine

Lösungsmittel

dioxane

water

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionthe mixture was extracted with 400 ml of ethyl acetate
2. 2
   ExtraktionThe organic layer was extracted with 100 ml of a 5% aqueous solution of sodium hydrogencarbonate
3. 3
   Temperaturcooling
4. 4
   Extraktionextracted with ethyl acetate
5. 5
   WaschenThe organic layer was washed with an aqueous solution of potassium hydrogensulfate
6. 6
   Trocknena saturated aqueous solution of sodium chloride, and dried over magnesium sulfate
7. 7
   workup.DISTILLATIONThe solvent was distilled off
8. 8
   FiltrationThe thus-obtained crystals were collected by filtration with ethyl acetate/hexane

Vorschrift

To 33.4 g (0.2 mol) of p-hydroxyphenylglycine were added 110 ml of water, 42 ml (1.5 eq.) of triethylamine, 52.8 g (1.1 eq.) of S-t-butoxycarbonyl-4,6-dimethyl-2-mercaptopyrimidine and 110 ml of dioxane, and the mixture was stirred at room temperature for 14 hours. To the reaction mixture was added 300 ml of water, and the mixture was extracted with 400 ml of ethyl acetate. The organic layer was extracted with 100 ml of a 5% aqueous solution of sodium hydrogencarbonate. The aqueous layers were combined, adjusted to pH 3 with 5N hydrochloric acid under ice-cooling and extracted with ethyl acetate. The organic layer was washed with an aqueous solution of potassium hydrogensulfate and a saturated aqueous solution of sodium chloride, and dried over magnesium sulfate. The solvent was distilled off. The thus-obtained crystals were collected by filtration with ethyl acetate/hexane. Yield: 46.0 g (86.1%).

Quelle