Reaktion #738959

Reaktionsgleichung

pentafluorophenol

1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride

hydrazine hydrochloride

(E)-2(R)-[1(S)-(tert-butoxycarbonyl)-4-phenyl-3-butenyl]-4-methylvaleric acid

→

(E)-2(R)-[1(S)-(tert-butoxycarbonyl)-4-phenyl-3-butenyl]-4-methylvalerohydrazide

Lösungsmittel

ethyl acetate

triethylamine

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITThe mixture was left
2. 2
   Temperaturto warm to room temperature
3. 3
   workup.STIRRINGwas then stirred overnight
4. 4
   SonstigeEvaporation
5. 5
   Sonstigegave a residue which
6. 6
   Waschenwashed with 2M aqueous hydrogen chloride, 5% aqueous sodium hydrogen carbonate and saturated aqueous sodium chloride
7. 7
   SonstigeEvaporation
8. 8
   Sonstigegave a solid which
9. 9
   Waschenwas washed with ether/hexane (1:1)
10. 10
    Sonstigedried

Vorschrift

A solution of 20 g of (E)-2(R)-[1(S)-(tert-butoxycarbonyl)-4-phenyl-3-butenyl]-4-methylvaleric acid in 200 ml of dimethylformamide was cooled to 0° C. under nitrogen and treated with 11.8 g of pentafluorophenol and 12.3 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride. The mixture was stirred for 2.5 hours at 0° C. and then treated with 19.8 g of hydrazine hydrochloride and 33 ml of triethylamine. The mixture was left to warm to room temperature and was then stirred overnight. Evaporation gave a residue which was dissolved in ethyl acetate and washed with 2M aqueous hydrogen chloride, 5% aqueous sodium hydrogen carbonate and saturated aqueous sodium chloride. Evaporation gave a solid which was washed with ether/hexane (1:1) and dried to give 12.1 g of of (E)-2(R)-[1(S)-(tert-butoxycarbonyl)-4-phenyl-3-butenyl]-4-methylvalerohydrazide in the form of a white solid.

Quelle