Acetic Anhydride → 6-Amino-1-propyluracil

Participants

Reaction Steps

To a solution of 47 g. (0.55 mol) cyanoacetic acid and 100 ml of acetic anhydride was added 50 g (0.49 mol) of n-propylurea. The solution was stirred at 60°-70° C. for 1 hour. After cooling, white crystals were filtered off and washed with ethanol. Yield 56.2 g (68%) (I). This was stirred in 100 ml of hot water and 60 ml of 2 N NaOH was added in portions so the solution the whole time was basic. The reaction mixture was refluxed for 20 minutes and then neutralized with 5 N HCl. After cooling, white crystals were filtered off. Yield 34.3 g (61%) (II) NMR.

Provenance & Evidence