Citric Acid → Sildenafil Citrate

Participants

Reaction Steps

In a 3-necked flask, sildenafil (5 g, 10 mmol) and citric acid (2 g, 10 mmol) were suspended in acetone (100 ml). The reaction mixture was heated to reflux and maintained at reflux for 1 hour, thereafter, the reaction mixture was allowed to cool for 3 hours to room temperature. The precipitate was collected by filtration and dried at 50° C. under 10 mm Hg to give pure sildenafil citrate in 94.4% yield.

Provenance & Evidence