Diisopropylethylamine → (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)-N'-(quinoxalin-2-yl)acrylohydrazide

Participants

Reaction Steps

A 50-mL, 3-necked, round-bottomed flask was charged with a solution of (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)acrylic acid (0.25 g) and 2-hydrazinylquinoxaline (0.14 g, 1.2 eq.) in EtOAc. T3P (50% in EtOAc; 0.83 mL, 2.0 eq.) and DIPEA (0.5 mL, 4.0 eq.) were added under nitrogen atmosphere at −55 to −60° C. and the reaction mixture was stirred for 2 hr before being concentrated under reduced pressure (25° C., 20 mmHg) to afford 0.150 g of crude solid. Purification using Combi-Flash column chromatography (eluting with MeOH:CH2Cl2; desired compound started eluting at 5% MeOH in CH2Cl2) afforded 60 mg (yield: 20%) (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)-N′-(quinoxalin-2-yl)acrylohydrazide. 1H NMR (400 MHz, DMSO-d6) δ=10.851 (s, 1H), 9.89-9.87 (s, 1H), 9.67 (s, 1H), 8.49-8.54 (m, 3H), 8.26 (s, 1H), 8.28 (s, 1H), 7.86-7.88 (d, J=8 Hz, 1H), 7.45-7.66 (m, 4H), 6.17-6.20 (d, J=10.4 Hz, 1H); LCMS for C21H14F6N7O [M+H]+ 494.37; found 494.19 (RT 2.88 min, purity: 100%).

Provenance & Evidence