Reaction #86641

Reaction equation

Methyl ester

(S)-2-[(S)-3-(4-Allyloxy-phenyl)-2-(4-fluoro-benzenesulfonylamino)-propionylamino]-4-methyl-pentanoic acid methyl ester

Sodium hydroxide

Methanol

→

(S)-2-[(S)-3-(4-Allyloxy-phenyl)-2-(4-fluoro-benzenesulfonylamino)-propionylamino]-4-methyl-pentanoic acid

Solvents

THF

water

Conditions

Workup

1. 1
   workup.ADDITIONwas added
2. 2
   Otherto obtain a homogenous solution
3. 3
   Concentrationbefore being concentrated in vacuo
4. 4
   OtherThe residue was partitioned between EtOAc and 1M hydrochloric acid
5. 5
   ExtractionThe aqueous phase was extracted twice more with EtOAc
6. 6
   Washthe combined organic extracts were washed with brine
7. 7
   Dryingdried (MgSO4)
8. 8
   Filtrationfiltered
9. 9
   Concentrationconcentrated in vacuo
10. 10
    Otherto yield a white foam, 2.50 g, 95%

Procedure

Methyl ester 11 (2.70 g, 5.33 mmol) was dissolved in THF (30 mL). Sodium hydroxide (0.853 g, 21.3 mmol) pre-dissolved in water (10 mL) was added. Methanol (15 mL) was added to obtain a homogenous solution and this was stirred at rt for 18 h before being concentrated in vacuo. The residue was partitioned between EtOAc and 1M hydrochloric acid. The aqueous phase was extracted twice more with EtOAc and the combined organic extracts were washed with brine, dried (MgSO4), filtered and concentrated in vacuo to yield a white foam, 2.50 g, 95%.

Source