Acetic Anhydride → Nalpha-Acetyl-p-Nitro-L-Phenylalanine Methyl Ester

Participants

Reaction Steps

Compound 2 (4.10 g, 15.7 mmol) was suspended in a mixture of distilled pyridine (40 ml) and acetic anhydride (5 ml). A solution formed after several minutes, and stirring was continued overnight. The solvent was evaporated, and the residue was dissolved in ethyl acetate. The solution was then extracted with 0.1N HCl, 1M sodium bicarbonate, and water and dried (MgSO4). Precipitation with hexanes gave 3.57 g (85.1%) of a solid melting at 113°-117° C. Recrystallization from ethyl acetate/hexanes gave 2.75 g, mp 118°-120° C., [α]D25 =+15.1° (c=2.1, ethanol).

Provenance & Evidence