Reaction #75559

Reaction equation

H-Pro-OBzl

Boc-Val-OH

HOBt

NMM

DCC

→

Boc-Val-Pro-OBzl

Solvents

chloroform

Conditions

Workup

1. 1
   FiltrationThe mixture was filtered
2. 2
   Othersolvent was evaporated
3. 3
   workup.ADDITIONEthyl acetate was added
4. 4
   Otherinsoluble material was removed by filtration
5. 5
   WashThe filtrate was washed with 0.2N HCl, 5% NaHCO3, and saturated aqueous NaCl
6. 6
   DryingIt was dried over Na2SO4
7. 7
   Filtrationfiltered
8. 8
   Otherevaporate

Procedure

Boc-Val-Pro-OBzl was prepared by dissolving H-Pro-OBzl (20 g, 83 mmol) in 50 mL of chloroform and adding Boc-Val-OH (18.0 g, 83 mmol), HOBt (23.0g, 165 mmol), NMM ( 9.0 mL, 83 mmol) and DCC (17.0 g, 83 mmol). The reaction mixture was stirred overnight at room temperature. The mixture was filtered and solvent was evaporated. Ethyl acetate was added and insoluble material was removed by filtration. The filtrate was washed with 0.2N HCl, 5% NaHCO3, and saturated aqueous NaCl. It was dried over Na2SO4, filtered and evaporate to give a white solid (30 g, 75 mmol, 90%). ESI/MS calculated for C22H32N2O5 +H: 405.2. Found 405.6.

Source