Reacción #1867

Ecuación de reacción

trans- 7-chloro-5-(2-chlorophenyl)-1-isobutyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid

pivaloyloxymethyl chloride

N,N-diisobutyl ethylamine

water

→

trans-7-chloro-5-(2-chlorophenyl)-1-isobutyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid pivaloyloxymethyl ester

Disolventes

N,N-dimethylformamide

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   Extracciónfollowed by extraction
2. 2
   LavadoThe ethyl acetate layer was washed with an aqueous solution of potassium hydrogensulfate
3. 3
   Secadoan aqueous solution of sodium hydrogencarbonate and water, successively, which was dried over anhydrous magnesium sulfate
4. 4
   workup.DISTILLATIONThe solvent was then distilled off under reduced pressure
5. 5
   OtroThe residue was purified by means of a silica gel column chromatography (hexane:ethyl acetate=10:1 to 5:1)

Procedimiento

In N,N-dimethylformamide (10 ml) was dissolved trans- 7-chloro-5-(2-chlorophenyl)-1-isobutyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid (0.5 g) obtained in Example 2. To the solution were added pivaloyloxymethyl chloride (0.43 ml), N,N-diisobutyl ethylamine (0.52 ml) and KI (0.2 g). The mixture was stirred at room temperature overnight. To the reaction mixture were added water (100 ml) and ethyl acetate (100 ml), followed by extraction. The ethyl acetate layer was washed with an aqueous solution of potassium hydrogensulfate, an aqueous solution of sodium hydrogencarbonate and water, successively, which was dried over anhydrous magnesium sulfate. The solvent was then distilled off under reduced pressure. The residue was purified by means of a silica gel column chromatography (hexane:ethyl acetate=10:1 to 5:1) to afford trans-7-chloro-5-(2-chlorophenyl)-1-isobutyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid pivaloyloxymethyl ester (0.55 g).

Fuente