1-Hydroxybenzotriazole → Boc-Val-Pro-OBzl

Participants

Reaction Steps

To a solution of N-(tert-butoxycarbonyl)-L-valine (10.86 g) and L-proline benzyl ester hydrochloride (12.09 g) in DMF (50 ml) were added HOBT (6.76 g) and WSCD (7.76 g) under ice-bath cooling. After being stirred at room temperature for 18 hours, the reaction mixture was concentrated under reduced pressure. The residue was dissolved in ethyl acetate (400 ml) and washed with 5% aqueous citric acid (200 ml) saturated aqueous sodium bicarbonate (200 ml). The solution was dried over magnesium sulfate and evaporated under reduced pressure to give N-(tert-butoxycarbonyl)-L-valyl-L-proline benzyl ester (20.06 g) as an oil.

Provenance & Evidence