1,3-Dimethyluracil → Pyrazolo[1,5-a]pyriMidin-5(4H)-one

Participants

Reaction Conditions

Reaction Steps

1,3-Dimethyl uracil (3.15 g, 22.5 mmol) and sodium ethoxide (23 mL of a 21% solution in ethanol) were added to a solution of 1H-pyrazol-5-amine (1.7 g, 20.4 mmol) in ethanol (50 mL). The resulting mixture was heated to 60° C. for 2 h and was then cooled to room temperature. The pale brown solid was isolated by filtration to give pyrazolo[1,5-a]pyrimidin-5(4H)-one (1.6 g, 58%). Retention time (min)=0.820, method [3], MS (ESI) 136.1 (M+H).

Provenance & Evidence