Reaktion #4558

Reaktionsgleichung

acetic acid

DIBAL-H

4-(4-(4-bromo-2-fluorophenoxy)phenoxy)-3-methoxy-2-pentenoic acid, methyl ester

ether

→

product

Ausbeute 74.0%

4-(4-(4-Bromo-2-fluorophenoxy)phenoxy)-3-methoxy-2-penten-1-ol

Ausbeute 74.0%

Lösungsmittel

toluene

water

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe temperature below -60° C
2. 2
   Sonstigethe temperature below -60° C
3. 3
   Temperaturto warm to room temperature
4. 4
   Filtrationthe solid material was filtered off
5. 5
   WaschenThe filtrate was washed twice with saturated NaHCO3 and once with water
6. 6
   Trocknendried over MgSO4
7. 7
   Sonstigethe solvent was removed by rotary evaporation
8. 8
   SonstigeThe residue was purified by HPLC
9. 9
   Wascheneluting with 80:20 hexane

Vorschrift

To a solution of 4.5 g (10.6 mmol) 4-(4-(4-bromo-2-fluorophenoxy)phenoxy)-3-methoxy-2-pentenoic acid, methyl ester in 25 ml toluene at -78° C. was added dropwise over a period of 30 min, 16.5 ml of 1.5M DIBAL-H in toluene, keeping the temperature below -60° C. The mixture was stirred for 21/2 hours at -78° C. To the mixture was added 17 ml of a 75:25:6 ether:acetic acid:water mixture, keeping the temperature below -60° C. The mixture was then allowed to warm to room temperature and the solid material was filtered off. The filtrate was washed twice with saturated NaHCO3 and once with water, dried over MgSO4 and the solvent was removed by rotary evaporation. The residue was purified by HPLC, eluting with 80:20 hexane:acetone, to give 3.1 g (74%) of the product as a pale yellow oil which was used immediately in the next reaction.

Quelle