Water → Sitagliptin phosphate monohydrate

Participants

Reaction Conditions

Reaction Steps

10 g Sitagliptin base was charged with 180 ml of isopropyl acetate, 50 ml isopropanol and 5 ml water at 20-25° C. under stirring to get a clear solution, followed by dropwise addition of a solution of 3.4 g phosphoric acid dissolved in 20 ml of isopropyl acetate over a period of 30 minutes. The reaction mixture was stirred for 5 minutes and then refluxed at 76-77° C. for 2 hours. The reaction mixture was cooled gradually to 20-25° C., stirred for 16-18 hours and then filtered, washed with isopropyl acetate and dried in oven under vacuum at 50° C. for 20-24 hours.

Provenance & Evidence