Reaction #969878

Reaction equation

triethylamine

BOP

Z-Val-Pro-OH

H-Val-Pro-OtBu.HCl

→

Z-Val-Pro-Val-Pro-OtBu

Yield 68.0%

Solvents

dichloromethane

Conditions

Workup

1. 1
   OtherThen, the solvent was evaporated
2. 2
   workup.DISSOLUTIONthe residue was dissolved in dichloromethane
3. 3
   Washwashed with citric acid (10%), NaHCO3 (10%) and brine
4. 4
   DryingThe organic layer was dried (Na2SO4)
5. 5
   Otherevaporated to dryness
6. 6
   Otherleaving a residue that
7. 7
   Otherwas purified on a column chromatography with hexane-ethyl acetate, 2:1
8. 8
   Otherto give X (68% yield)

Procedure

A solution of Z-Val-Pro-OH (681.3 mg, 1.95 mmol) in dichloromethane (6 mL), was successively treated at room temperature. with (benzotriazol-1-yloxy)tris(dimethylamino)phosphoniun hexafluorophale (BOP) (865.1 mg, 1.95 mmol), H-Val-Pro-OtBu.HCl (500 mg, 1.63 mmol) and triethylamine (TEA) (500 μL, 3.58 mmol). The mixture was stirred overnight at room temperature. Then, the solvent was evaporated, the residue was dissolved in dichloromethane and washed with citric acid (10%), NaHCO3 (10%) and brine. The organic layer was dried (Na2SO4) and evaporated to dryness leaving a residue that was purified on a column chromatography with hexane-ethyl acetate, 2:1 to give X (68% yield).

Source