Reaktion #1334555

Reaktionsgleichung

HCl

(RS)-(2,6-difluoro-4-hydroxy-phenyl)-ethoxy-acetic acid ethyl ester

Tf2O

→

(RS)-(2,6-difluoro-4-trifluoromethanesulfonyloxy-phenyl)-ethoxy-acetic acid ethyl ester

Ausbeute 98.0%

Lösungsmittel

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITthe resulting solution was left
2. 2
   ExtraktionThe product was extracted with AcOEt
3. 3
   WaschenThe organic layer was washed with more 1 N HCl (50 ml), water (50 ml) and brine (30 ml)
4. 4
   ExtraktionThe aqueous layers were extracted with more AcOEt
5. 5
   TrocknenAfter drying (MgSO4) the solvent
6. 6
   Sonstigewas evaporated

Vorschrift

A solution of (RS)-(2,6-difluoro-4-hydroxy-phenyl)-ethoxy-acetic acid ethyl ester (500 mg) in pyridine (5 ml) was placed under N2 and cooled to 0° C. Tf2O (813 mg) was added and the resulting solution was left to stir in the ice bath. After 18 h the reaction mixture was poured on a mixture of 50 ml 1 N HCl and ice. The product was extracted with AcOEt. The organic layer was washed with more 1 N HCl (50 ml), water (50 ml) and brine (30 ml). The aqueous layers were extracted with more AcOEt. After drying (MgSO4) the solvent was evaporated to obtain 738 mg (98%) of (RS)-(2,6-difluoro-4-trifluoromethanesulfonyloxy-phenyl)-ethoxy-acetic acid ethyl ester. Yellow oil. MS 393.4 ([M+H]+).

Quelle