Reaction #74262

Reaction equation

(−)-(4-Chloro-phenyl)-(R)-(3-trifluoromethyl-phenoxy)-acetic acid 2-acetylamino-ethyl ester

→

title compound

(−)-(4-Chloro-phenyl)-(3-trifluoromethyl-phenoxy)-acetic acid 2-acetylamino-ethyl ester

Solvents

diisopropylether

Conditions

Workup

1. 1
   Filtrationfiltered
2. 2
   Temperaturecooled to 35° C. over 4 hours
3. 3
   workup.STIRRINGstirred at 35° C. for 2 hours
4. 4
   Otherto yield a thick suspension
5. 5
   TemperatureThe suspension was cooled to −5° C. over about 5 hours
6. 6
   workup.STIRRINGstirred at −5° C
7. 7
   FiltrationThe resulting crystals were filtered off with a centrifuge
8. 8
   Washwashed with precooled (−5° C.) diisopropylether (100 mL)
9. 9
   OtherThe wet product was dried at 30° C.

Procedure

(−)-(4-Chloro-phenyl)-(R)-(3-trifluoromethyl-phenoxy)-acetic acid 2-acetylamino-ethyl ester (90.0 g) was dissolved in diisopropylether (900 mL) at 55° C. The resulting mixture was polish filtered, the solution cooled to 44° C. over about 20 minutes and seeded. The resulting mixture was stirred for 1 hour at 44° C., cooled to 35° C. over 4 hours, then stirred at 35° C. for 2 hours to yield a thick suspension. The suspension was cooled to −5° C. over about 5 hours and then stirred at −5° C. The resulting crystals were filtered off with a centrifuge and washed with precooled (−5° C.) diisopropylether (100 mL). The wet product was dried at 30° C. to yield the title compound as a white crystalline solid, more specifically as white crystals, needles.

Source