Reaction #1875

Reaction equation

hydrochloric acid

cis-1-benzyl-2-oxo-5-phenyl-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-propionic acid

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

sodium hydroxide

→

cis-1-benzyl-2-oxo-5-phenyl-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-propionic acid

Solvents

methanol

Conditions

Workup

1. 1
   Extractionwas subjected to extraction with 150 ml of ethyl acetate
2. 2
   WashThe ethyl acetate layer was washed with water
3. 3
   Dryingdried over anhydrous magnesium sulfate
4. 4
   workup.DISTILLATIONThen the solvent was distilled off under reduced pressure

Procedure

In 20 ml of methanol was dissolved 0.5 g of ethyl ester of cis-1-benzyl-2-oxo-5-phenyl-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-propionic acid obtained in Example 8. To the solution was added 7 ml of 1N sodium hydroxide, and the mixture was stirred for 30 minutes at room temperature. The reaction mixture was acidified with 100 ml of 1N hydrochloric acid, which was subjected to extraction with 150 ml of ethyl acetate. The ethyl acetate layer was washed with water and dried over anhydrous magnesium sulfate. Then the solvent was distilled off under reduced pressure to leave 0.46 g of cis-1-benzyl-2-oxo-5-phenyl-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-propionic acid as plates, m.p. 112°-114° C.

Source