Reacción #45289

Ecuación de reacción

2,2,2-trifluoro-1(RS)-(4-fluorophenyl)ethanol

trifluoromethanesulfonyl chloride

sodium hydride

→

trifluor-methanesulfonic acid 2,2,2-trifluoro-1(RS)-(4-fluorophenyl)ethyl ester

Rendimiento 74.9%

Disolventes

ethyl ether

ethyl ether

Condiciones de reacción

Tratamiento posterior

1. 1
   Lavadowashed with dried hexane (20 mL) twice
2. 2
   workup.ADDITIONDried ethyl ether (10 mL) was added
3. 3
   workup.ADDITIONAfter completion of addition
4. 4
   workup.ADDITIONAfter completion of addition
5. 5
   Temperaturato warm up to room temperature
6. 6
   workup.STIRRINGstirred for 1 h
7. 7
   OtroThe solvent was removed under rot-vap
8. 8
   workup.ADDITIONdiluted with hexane (150 mL)
9. 9
   Lavadowashed with a saturated NaHCO3 n and brine
10. 10
    SecadoAfter drying with MgSO4
11. 11
    Otrothe organic solvent was removed

Procedimiento

A dried 50 mL of flask was charged sodium hydride, 60% dispersion in mineral oil (624 mg, 15.6 mmol) under N2 and then washed with dried hexane (20 mL) twice. Dried ethyl ether (10 mL) was added and a solution of 2,2,2-trifluoro-1(RS)-(4-fluorophenyl)ethanol (90% ee) (2.5 g, 12.89 mmol) in ethyl ether (10 mL) was added at 0° C. After completion of addition, the reaction mixture was allowed to warm up to room temperature and stirred for 1 h. A solution of trifluoromethanesulfonyl chloride (3.28 g, 19.5 mmol) in ethyl ether (10 mL) was added at 0° C. After completion of addition, the reaction was allowed to warm up to room temperature and stirred for 1 h. The solvent was removed under rot-vap and diluted with hexane (150 mL) and washed with a saturated NaHCO3 n and brine. After drying with MgSO4, the organic solvent was removed to give trifluor-methanesulfonic acid 2,2,2-trifluoro-1(RS)-(4-fluorophenyl)ethyl ester (3.15 g) (90% ee) as a colorless oil which was used in the next step without further purification.

Fuente