Dimethylformamide → [2-(2,5-Dioxo-imidazolidin-1-yl)-ethyl]-carbamic acid tert-butyl ester

Participants

Reaction Steps

3-(2-Aminoethyl)-imidazolidine-2,4-dione hydrochloride (14.7 g., 82 mmol) was suspended in DCM (300 mL) and DIPEA (28 mL, 160 mmol) was added. The mixture was stirred for 15 min, and then BOC2O (19.7 g, 90 mmol) was added. The suspension was stirred for 1 h, and then DMF (45 mL) was added. The stirred suspension gradually became a clear solution over the next several h. Stirring was continued for a further 16 h, after which time a thick precipitate had formed. The mixture was concentrated to dryness in vacuo, ensuring the last traces of DMF were removed, and then dissolved in boiling EtOAc (200 mL). Hexane (800 mL) was added, the mixture cooled and allowed to stand for 1 h. The resulting product was collected by filtration. Yield=14.6 g, 73%.

Provenance & Evidence