Potassium Carbonate → 4-(4-bromophenyl)-5-{[1-(cyclopropylcarbonyl)-3-azetidinyl]methyl}-2,4-dihydro-3H-1,2,4-triazol-3-one

In a round bottom flask equipped with reflux condenser, a mixture of N-(4-bromophenyl)-2-{[1-(cyclopropylcarbonyl)-3-azetidinyl]acetyl}hydrazinecarboxamide (4.71 g, 5.48 mmol) and potassium carbonate (3.79 g, 27.4 mmol) in water (400 mL) was stirred at reflux (oil bath temp=130° C.) for 14 h. The reaction was cooled to room temperature. The reaction mixture was concentrated in vacuo and then taken up into ethyl acetate (250 mL) and water (100 mL). The pH of the mixture was adjusted to ˜5-5.5 (pH paper) using 1N aq HCl solution and then the layers were separated. The aqueous layer was extracted with ethyl acetate (2×150 mL). The organic layers were combined, dried over MgSO4, and concentrated in vacuo. Purification of the residue by silica gel chromatography (0-10% methanol/ethyl acetate) followed by drying in a vacuum oven (70° C.) overnight provided the title compound as a white solid (0.93 g, 38.7%). MS(ES)+ m/e 377.0, 379.0 [M+H]+.