Urea → 6-Amino-3-methyl-1-phenylpyrimidine-2,4(1H,3H)-dione

Participants

Reaction Conditions

Reaction Steps

N-Methyl-N'-phenylurea was preliminarily prepared from phenyl isocyanate and methylamine by the procedure described in Step 1. Using the urea compound as the starting material, uracil ring was formed by the procedure described in Step 2. N-Methyl-N'-phenylurea (30 g, 0.2M) and cyanoacetic acid (18.8 g, 0.22M) were dissolved in 400 ml of a solvent, acetic anhydride, and heated at 80° C. for 2 hours. The solvent acetic anhydride was distilled off under reduced pressure and 200 ml of water was added to the residue, followed by cooling with ice. A 2N aqueous solution of NaOH (220 ml) was then added and the mixture was stirred for 2 hours. A precipitated solid product was obtained by filtration. The solid product was washed successively with water and methanol and dried to yield 6-amino-3-methyl-1-phenyluracil (yield: 33 g, or 76% based on N-methyl-N'-phenylurea).

Provenance & Evidence