Reaction #1902

Reaction equation

(3R,5S)-7-chloro-5-(2-methoxyphenyl)-1-neopentyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid

sodium hydroxide

→

sodium (3R,5S)-7-chloro-5-(2-methoxyphenyl)-1-neopentyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetate

Solvents

methanol

Conditions

Workup

1. 1
   workup.DISSOLUTIONAfter the acid was dissolved completely
2. 2
   Concentrationthe mixture was concentrated in vacuo
3. 3
   workup.ADDITIONTo the residue was added ethyl acetate (200 ml)
4. 4
   Concentrationthe mixture was concentrated in vacuo
5. 5
   OtherThe deposited crystals were collected

Procedure

To a suspension of (3R,5S)-7-chloro-5-(2-methoxyphenyl)-1-neopentyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetic acid (12 g) in methanol (200 ml) was added 1N aqueous sodium hydroxide (27.7 ml). After the acid was dissolved completely, the mixture was concentrated in vacuo. To the residue was added ethyl acetate (200 ml) and the mixture was concentrated in vacuo. The deposited crystals were collected to give sodium (3R,5S)-7-chloro-5-(2-methoxyphenyl)-1-neopentyl-2-oxo-1,2,3,5-tetrahydro-4,1-benzoxazepine-3-acetate (11.8 g) as colorless crystals (mp>300° C.).

Source