Phosphoric Acid → Sitagliptin Phosphate Monohydrate

Participants

Reaction Conditions

Reaction Steps

7-[(3R)-3-Amino-1-oxo-4-(2,4,5-trifluorophenyl)butyl]-5,6,7,8-tetrahydro-3-(trifluoromethyl)-1,2,4-triazolo[4,3-a]pyrazine of Formula II (0.4 g), isopropanol (5 mL), water (0.4 mL), and phosphoric acid (0.11 g) are charged and heated to about 70° C. for about 3 hours. The reaction mass is then cooled to about 30° C. and stirred for about 10 hours. The separated solid is filtered and dried at about 45° C. under vacuum for about 4 hours to afford the title compound. (Yield: 68%; purity by HPLC: 96.67%; purity by chiral HPLC: 99.19%; m/z: 408(m+1); SOR: −21° C. (c=1% in water))

Provenance & Evidence