1421923-86-5

1421923-96-7

54608-52-5

1421923-86-5

General procedure for the synthesis of (E)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)-N'-(pyrazin-2-yl)acrylhydrazide from the compound (CAS: 1421923-96-7) and pyrazin-2-hydrazine: 1. a solution was prepared by dissolving (E)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)acrylic acid (0.75 g) in EtOAc (25 mL) and THF (12.5 mL). 2. To the above solution, a solution of 2-hydrazinopyrazine (0.23 g) in THF (12 mL) was added dropwise at room temperature. 3. Subsequently, T3P (50% ethyl acetate solution, 1.52 mL) and DIPEA (1.46 mL) were added dropwise and the reaction mixture was stirred at room temperature for 30 minutes. 4. After completion of the reaction, the reaction was quenched with ice-cold water and extracted with EtOAc (3 x 25 mL). 5. The organic layers were combined, washed with brine and dried over anhydrous Na2SO4. 6. concentrated under reduced pressure (35 °C, 20 mmHg) to give 0.698 g of crude product. 7. The crude product was first ground with petroleum ether and then with Et2O to give 275 mg (yield: 29%) of the target compound. Product characterization: 1H NMR (400 MHz, DMSO-d6) δ: 10.3 (s, 1H), 9.15 (s, 2H), 8.59 (s, 2H), 8.30-8.26 (d, J = 14.8 Hz, 1H), 8.13 (s, 1H), 8.06-8.07 (m, 1H), 6.98-6.95 (d, J = 13.4 Hz. 1H); LCMS for C17H12F6N7O [M + H]+: 443.31; found: 444.19 (retention time: 2.625 min, purity: 99.06%).