Acetic Anhydride → 2-Acetylamino-4-oxo-4,5-dihydro-imidazole-1-carboxylic acid benzyl ester

Participants

Reaction Steps

To a suspension of 2-amino-4-oxo-4,5-dihydro-imidazole-1-carboxylic acid benzyl ester (46.6 mg, 0.20 mmol), Et3N (26.0 mg, 0.26 mmol) and DMAP (2.5 mg, 0.02 mmol) in CH2Cl2 (4 mL) was added dropwise Ac2O (24.5 mg, 0.24 mmol), and the reaction mixture was then heated to reflux under argon for 1 hr. Cooled to r.t., the reaction mixture was concentrated and the residue was partitioned between EtOAc and water. The organic layer was dried over Na2SO4 and concentrated to give 2-acetylamino-4-oxo-4,5-dihydro-imidazole-1-carboxylic acid benzyl ester as an oil (54.0 mg, 98.2%).

Provenance & Evidence