Diisopropylethylamine → (Z)-N'-(3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)acryloyl)-5-methyl-1H-pyrazole-4-carbohydrazide

Participants

Reaction Conditions

Reaction Steps

In a 50 mL, 3-neck round-bottom flask, (Z)-3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)acrylic acid (Example 1, Step 4; 0.5 g, 1.0 eq.) was dissolved in EtOAc:EtOH (15 mL, 2:1) and cooled to −60° C. where 5-methyl-1H-pyrazole-4-carbohydrazide (0.24 g, 1.0 eq.) was introduced dropwise. T3P (50% in EtOAc) (1.69 mL, 1.5 eq.) was added dropwise followed by DIPEA (2 mL, 8 eq.) and the reaction mixture was stirred for 1 h at −60° C. The reaction mixture was concentrated under reduced pressure (25° C., 20 mm Hg) to afford the crude product that was purified by column chromatography (60/120 silica gel) using methanol/dichloromethane gradient (the column was packed in dichloromethane and the desired compound started eluting from 3% methanol/dichloromethane). Fractions containing the desired compounds were combined to afford (Z)—N′-(3-(3-(3,5-bis(trifluoromethyl)phenyl)-1H-1,2,4-triazol-1-yl)acryloyl)-5-methyl-1H-pyrazole-4-carbohydrazide (0.2 g, yield: 42%).

Provenance & Evidence