Reaktion #44667

Reaktionsgleichung

(3R,5R)-3-((R)-1-hydroxyethyl)-5-(3,4,5-trifluorophenyl)morpholine-4-carboxylic acid benzyl ester

triethylamine

oxalyl chloride

dimethylsulfoxide

→

titled compound

Ausbeute 91.4%

(3R,5R)-3-acetyl-5-(3,4,5-trifluorophenyl)morpholine-4-carboxylic acid benzyl ester

Ausbeute 91.4%

Lösungsmittel

tetrahydrofuran

ammonium chloride

ethyl acetate

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas returned to room temperature
2. 2
   Sonstigethe organic layer was partitioned
3. 3
   TrocknenThe organic layer was dried over anhydrous magnesium sulfate
4. 4
   SonstigeSolvent was removed by distillation under reduced pressure
5. 5
   SonstigeThe resultant product was purified by silica gel column chromatography (heptane/ethyl acetate)

Vorschrift

A solution of dimethylsulfoxide (0.22 mL) in tetrahydrofuran (15 mL) was cooled to −78° C. and then oxalyl chloride (246 μL) was dropwise added thereto. The resultant solution was stirred at the same temperature for 5 minutes, and to the reaction mixture was then dropwise added a solution of (3R,5R)-3-((R)-1-hydroxyethyl)-5-(3,4,5-trifluorophenyl)morpholine-4-carboxylic acid benzyl ester (880 mg) in tetrahydrofuran (5 mL). The resultant solution was stirred at the same temperature for 1 hour, and triethylamine (1.54 mL) was then added thereto. The temperature of this solution was returned to room temperature. The solution was then stirred for 1 hour. The reaction solution was diluted with aqueous ammonium chloride and ethyl acetate, and the organic layer was partitioned. The organic layer was dried over anhydrous magnesium sulfate. Solvent was removed by distillation under reduced pressure. The resultant product was purified by silica gel column chromatography (heptane/ethyl acetate), to thereby obtain the titled compound (800 mg). The physical properties of this crude product were as follows.

Quelle