Potassium Carbonate → (S)-methyl 2-(((9H-fluoren-9-yl)methoxy)carbonylamino)-3-(4-nitrophenyl)propanoate

Participants

Reaction Steps

Fmoc-Cl (27.6 g, 107.2 mmol) in 1,4-dioxane (950 mL) was added dropwise to a solution of (S)-methyl 2-amino-3-(4-nitrophenyl)propanoate (3A; 20 g, 89.3 mmol) and K2CO3 (14.8 g , 107.2 mmol) in water (80 mL) and 1,4-dioxane (150 mL) on an ice bath. After being stirred for 2 hours at room temperature, the mixture was poured into 1.2 L of water to precipitate a white solid, which was filtered and washed with cold water. The solid was dried under vacuum for 3 hours to give 40 g of (S)-methyl 2-(((9H-fluoren-9-yl)methoxy)carbonylamino)-3-(4-nitrophenyl)propanoate 3B, which was directly used in step 2.

Provenance & Evidence